Absorbent article with dynamic elastic waist feature having a predisposed resilient flexural hinge

ABSTRACT

Absorbent article such as disposable diapers, incontinent briefs, diaper holders and the like, that have a unique elastic waist feature that improves the dynamic fit of the elasticized waistband as well as the containment characteristics of the absorbent article. The elastic waist feature preferably comprises an interconnecting panel zone, a first flexural hinge zone joining the interconnecting panel zone with the containment assembly, an elasticized waistband, and a second flexural hinge zone joining the elasticized waistband with the interconnecting panel zone. The elasticized waistband comprises a shaping panel zone; a waistline panel zone; and a predisposed, resilient, waistband flexural hinge zone joining the shaping panel zone and the waistline panel zone. The waistband flexural hinge zone is predisposed to allow the panel zones to flexurally bend about a defined axis or zone and is resilient to provide a restoring force/moment that returns the panel zones to their preceeding in-use configuration, especially when the elasticized waistband has been pretensioned by a closure system. The closure system dynamically creates/maintains lateral tension through the elasticized waistband thereby allowing the elasticized waistband to more dynamically expand and contract with the motions of the wearer. The absorbent article additionally preferably comprises a pair of elasticized side panels disposed in the second waist region. The elasticized side panels preferably comprise a &#34;zero strain&#34; stretch laminate and an extension panel. The present invention also relates to alternative waist features comprising &#34;an expansive tummy panel&#34; elasticized waistband.

This is a divisional of application Ser. No. 08/466,952, filed on Jun.6, 1995; which is a divisional of application Ser. No. 08/078,538, filedon Jun. 17, 1993, now U.S. Pat. No. 5,499,978, which is a continuationof application Ser. No. 07/914/958, filed Jul. 16, 1992, now U.S. Pat.No. 5,221,274; which is a continuation of application Ser. No.07/750,775, filed on Aug. 22, 1991, now U.S. Pat. No. 5,151,092; whichis a continuation-in-part of application Ser. No. 07/715,152, filed onJun. 13, 1991, now abandoned.

FIELD OF THE INVENTION

The present invention relates to absorbent articles such as diapers,incontinent briefs, diaper holders, and the like, and more particularly,to absorbent articles having elastic waist features providing dynamicfit about the wearer as well as improved containment characteristics ofthe absorbent article.

BACKGROUND OF THE INVENTION

Infants and other incontinent individuals wear absorbent articles suchas diapers to receive and contain urine and other body exudates.Absorbent articles function both to contain the discharged materials andto isolate these materials from the body of the wearer and from thewearer's garments and bed clothing. Disposable absorbent articles havingmany different basic designs are known to the art. For example, U.S.Pat. No. Re. 26,152, entitled "Disposable Diaper" issued to Duncan andBaker on Jan. 31, 1967, describes a disposable diaper which has achievedwide acceptance and commercial success. U.S. Pat. No. 3,860,003,entitled "Contractable Side Portions For Disposable Diaper", issued toBuell on Jan. 14, 1975, describes an elasticized leg cuff disposablediaper which has achieved wide acceptance and commercial success.

However, absorbent articles have a tendency to sag or gap away from andto slide/slip down on the body of the wearer during wear. Thissagging/gapping and sliding/slipping is caused by the relative motionsof the wearer as the wearer breathes, moves and changes positions, bythe downward forces generated when the absorbent article is leaded withbody exudates, and by the deformation of the materials of the absorbentarticle itself when subjected to such wearer's motions. Thissagging/gapping and sliding/slipping of the absorbent article can leadto premature leakage and poor fit of the absorbent article about thewearer in the waist regions and the leg regions of the absorbentarticle.

In order to more snugly fit absorbent articles about the waist of thewearer, certain commercially available absorbent articles have beenprovided with elastic waist features. An example of a disposable diaperwith an elastic waist feature which has achieved wide acceptance andcommercial success is disclosed in U.S. Pat. No. 4,515,595 issued toKievit and Osterhage on May 7, 1985. Elastic waist features willtypically comprise an elasticized waistband consisting of an elasticmember contractibly affixed between the topsheet and the backsheet. Theelasticized waistband is, thus, designed to expand and contract with thewearer's motions and to maintain the fit of the absorbent article aboutthe waist of the wearer during use (i.e., provide sustained dynamicfit).

However, it has been found that absorbent articles having elastic waistfeatures also have a tendency to sag/gap and slide/slip during use.Further, the elastic waist feature has a tendency to rollover or roll-inat the front of the diaper resulting in a lack of fit about the waist ofthe wearer.

Thus, it would be advantageous to provide an absorbent article having anelastic waist feature that provides better fit, reduced leakage, andwearer comfort. It would further be advantageous to provide an absorbentarticle which has reduced sagging, gapping, rollover, or roll-in at thewaist of the diaper as well as reduced overall sliding/slipping of theabsorbent article or the absorbent core on the wearer during use.

Therefore, it is an object of the present invention to provide anabsorbent article having sustained dynamic fit about the waist of thewearer during use.

It is a further object of the present Invention to provide an absorbentarticle having a unique elastic waist feature that provides sustaineddynamic fit and improved resistance to leakage during use.

It is a still further object of the present Invention to provide anabsorbent article having a unique elastic waist feature which reducessagging, gapping, rollover or roll-in at the front of the diaper as wellas overall sliding/slipping of the absorbent article or the absorbentcore during use.

It is an another object of the present invention to provide a uniqueelastic waist feature having an elasticized waistband that provides suchsustained dynamic fit by providing a predisposed, resilient, waistbandflexural hinge zone which allows relative flexural bending between zonesof the elasticized waistband and provides a restoring force/moment toresiliently return the zones to essentially their preceding in-useconfiguration.

It is a further object of the present Invention to provide a closuresystem that maintains/creates lateral tension through at least a portionof the unique elastic waist feature to enhance the sustained dynamicfit.

These and other objects of the present Invention will be more readilyapparent when considered in reference to the following description andwhen taken in conjunction with the accompanying drawings.

SUMMARY OF THE INVENTION

The present invention provides absorbent articles such as disposablediapers, incontinent briefs, diaper holders and the like, that have aunique elastic waist feature that improves the dynamic fit of theelasticized waistband as well as the containment characteristics of theabsorbent article. Such absorbent articles comprise a containmentassembly preferably comprising a liquid pervious topsheet, a liquidimpervious backsheet, and an absorbent core positioned between thetopsheet and the backsheet; an elastic waist feature; and a closuresystem for creating/maintaining lateral tension through at least aportion of the elastic waist feature.

The elastic waist feature preferably comprises an interconnecting panelzone, a first flexural hinge zone joining the interconnecting panel zonewith the containment assembly, an elasticized waistband, and a secondflexural hinge zone joining the elasticized waistband with theinterconnecting panel zone. The elasticized waistband comprises ashaping panel zone; a waistline panel zone; and a predisposed,resilient, waistband flexural hinge zone joining the shaping panel zoneand the waistline panel zone. The interconnecting panel zone provides aflexible link between the elasticized waistband and the containmentassembly to allow rotations and translations of the elasticizedwaistband so that the elasticized waistband may move in functionalcontacting position and conform with the waist of the wearer. Theelasticized waistband is designed to elastically expand and contract andto dynamically fit the wearer's waist. The waistband flexural hinge zoneis predisposed to allow the panel zones to flexurally bend about adefined axes or zone and is resilient to provide a restoringforce/moment that returns the panel zones to their preceding in-useconfiguration, especially when the elasticized waistband has beenpretensioned by the closure system. Thus, the elastic waist featuremoves with and conforms to the waist of the wearer as the wearer sits,stands or moves. The elasticized waistband preferably comprises aportion of the topsheet, a portion of the backsheet that is preferablyprestrained, an elastomeric member, and a resilient member that enhancesthe resiliency for the waistband flexural hinge zone.

The absorbent article is also preferably provided with a closure system(tensioning means) for dynamically creating/maintaining lateral tensionthrough the elasticized waistband. The lateral tension dynamicallycreated and maintained by the closure system "activates" the stretch ofthe elasticized waistband thereby allowing it to more dynamically expandand contract with the motions of the wearer. The closure systempreferably comprises a dual tension fastening system. The dual tensionfastening system comprises a primary fastening system for forming a sideclosure and a waist closure system for forming a waist closure. Theprimary fastening system maintains the first waist region and the secondwaist region in an overlapping configuration such that lateral tensionsare maintained around the circumference of the diaper to maintain thediaper on the wearer. The primary fastening system comprises asecurement member, preferably a tape tab and a first fasteningcomponent, and a landing member preferably comprising a second fasteningcomponent to provide a variable positioning side closure. The waistclosure system forms a waist closure that anchors a portion of the endedge of the absorbent article and that dynamically maintains/createslateral tensions through the elasticized waistband so as to improve thefit and containment characteristics of the diaper by reducing gapping,sagging, and rollover of the elasticized waistband. The waist closuresystem comprises at least one, preferably a pair of, first attachmentcomponent(s) longitudinally aligned with the elasticized waistband andat least one second attachment component. Each attachment componentcomprises a fastening means that engages a complementary fastening meansfor providing a variable positioning, passively activated, waistclosure. The first attachment component(s) preferably comprise a hookfastening material while the second attachment component preferablycomprises a loop fastening material.

In an especially preferred embodiment of the present invention, theabsorbent article additionally comprises a pair of elasticized sidepanels disposed in the second waist region. The elasticized side panelsprovide an elastically extensible feature that provides a morecomfortable and contouring fit by initially conformably fitting thediaper to the wearer and by sustaining this fit. The elasticized sidepanels further develop and maintain wearing forces (tensions) thatenhance the tensions developed and maintained by both the primaryfastening system and the waist closure system. The elasticized sidepanels especially assist in pretensioning the elasticized waistband andfurther provide more effective application of the diaper. While eachelasticized side panel may be constructed in a number of configurations,the elasticized side panel preferably comprises a "zero strain" stretchlaminate. The elasticized side panel also preferably has an extensionpanel adjacent the leg of the wearer so that tensional forces throughthe side panel are not concentrated so as to prevent the indentation,rubbing, or chafing of the wearer's skin during use.

The present invention also relates to alternative elastic waist featurescomprising an "expansive tummy panel" elasticized waistband. In theseembodiments the elasticized waistband is capable of expanding wellbeyond the dimensions of the absorbent article set by the primaryfastening system (beyond the planar state of the diaper itself) so as toaccommodate wearers, especially large infants, with large expansilewaists so as to reduce the sagging/slipping of the absorbent article.The extension forces of the elasticized waistband are lower than theextension forces of the elasticized side panels so as to accomodate suchexpansion. In a preferred embodiment of this elastic waist feature, theelasticized waistband is formed from a stretch laminate. The stretchlaminate is comprised of an elastomeric member and a portion of thetopsheet and the backsheet which all have been mechanically stretched.In a preferred embodiment, the waistline panel zone is formed byremoving a portion of the backsheet (windowing). The shape of theelasticized waistband also provides differential extensibility in thelateral direction.

BRIEF DESCRIPTION OF THE DRAWINGS

While the specification concludes with claims particularly pointing outand distinctly claiming the subject matter which is regarded as formingthe present invention, it is believed that the invention will be betterunderstood from the following description which is taken in conjunctionwith the accompanying drawings in which like designations are used todesignate substantially identical elements, and in which:

FIG. 1 is a plan view of a disposable diaper embodiment of the presentinvention having portions cut-away to reveal underlying structure, theouter surface of the diaper facing the viewer;

FIG. 2 is a fragmentary sectional view of the disposable diaper shown inFIG. 1 taken along section line 2--2 of FIG. 1;

FIG. 2A is a plan view of the prestrained backsheet portion of thedisposable diaper showing the pattern of the mechanical stretching;

FIG. 2B is a simplified, fragmentary, enlarged plan view of thedisposable diaper of the present invention in the first waist regionshowing the elements of the elastic waist feature;

FIG. 3 is a fragmentary sectional view of the disposable diaper shown inFIG. 1 taken along section line 3--3 of FIG. 1;

FIGS. 4A-4D are simplified kinematic representations of the functioningof the elastic waist feature during use as the wearer (shown in thedrawings) moves from a standing position to a sitting position;

FIG. 5 is a fragmentary sectional view of an alternative disposablediaper embodiment of the present invention showing an alternativeconstruction of the elasticized waistband;

FIG. 5A is a fragmentary sectional view of a further alternativedisposable diaper embodiment of the present invention showing a furtheralternative construction of the elasticized waistband;

FIG. 6 is a fragmentary plan view of another alternative disposablediaper embodiment of the present invention showing an elastic waistfeature of an "expansive tummy panel" having differential extensibilityin the lateral direction and a "windowed" elastic waist feature;

FIG. 7 is a fragmentary plan view of an alternative embodiment of theelastic waist feature shown in FIG. 6;

FIG. 8 is a simplified perspective view of an apparatus that employs avacuum web restraint system for mechanically stretching a portion of adiaper web using meshing corrugated rolls;

FIG. 8A is a simplified view taken along line 8A-8A in FIG. 8 showingthe manner in which idler rolls are used to cause the diaper web to wrapthe lowermost corrugated rolls;

FIG. 8B is a highly enlarged view taken at the inset 8B shown in FIG. 8,showing the degree of meshing of the corrugated rolls with one anotheras the "zero strain" stretch laminate portion of the diaper web passestherebetween;

FIG. 9 is a simplified perspective view showing an alternative webrestraint system of the present invention which may be used during theincremental stretching process disclosed herein;

FIG. 9A is a highly enlarged simplified cross-sectional view taken atinset 9A shown in FIG. 9 along a centerline connecting the uppermostcorrugated rolls and the lowermost corrugated rolls;

FIG. 10 is a simplified, fragmentary, enlarged plan view of thedisposable diaper of the present invention in the first waist regionshowing the location for taking test samples from the elastic waistfeature;

FIG. 11 is a perspective view of a test apparatus for measuring thebending flexure recovery force of the waistband flexural hinge zone ofthe elastic waist feature;

FIG. 12 is a representative graph of deflection force versus deflectiondistance of two cycles of the flexure bending test;

FIG. 13 is a perspective view of the test sample created according tothe test procedures for determining the edge compression stiffness of apanel zone of the elastic waist feature;

FIG. 14 is a simplified side view of the apparatus and test sample "setup" for determining the edge compression stiffness of a panel zone ofthe elastic waist feature; and

FIG. 15 is a representative graph of compression force versuscompression displacement of two cycles of the edge compression stiffnesstest.

DETAILED DESCRIPTION OF THE INVENTION

As used herein, the term "absorbent article" refers to devices whichabsorb and contain body exudates, and, more specifically, refers todevices which are placed against or in proximity to the body of thewearer to absorb and contain the various exudates discharged from thebody. The term "disposable" is used herein to describe absorbentarticles which are not intended to be laundered or otherwise restored orreused as an absorbent article (i.e., they are intended to be discardedafter a single use and, preferably, to be recycled, composted orotherwise disposed of in an environmentally compatible manner). A"unitary" absorbent article refers to absorbent articles which areformed of separate parts united together to form a coordinated entity sothat they do not require separate manipulative parts like a separateholder and liner. A preferred embodiment of an absorbent article of thepresent invention is the unitary disposable absorbent article, diaper20, shown in FIG. 1. As used herein, the term "diaper" refers to anabsorbent article generally worn by infants and incontinent persons thatis worn about the lower torso of the wearer. It should be understood,however, that the present invention is also applicable to otherabsorbent articles such as incontinent briefs, incontinentundergarments, diaper holders and liners, feminine hygiene garments, andthe like.

FIG. 1 is a plan view of the diaper 20 of the present invention in itsflat-out, uncontracted state (i.e., with elastic induced contractionpulled out except in the side panels wherein the elastic is left in itsrelaxed condition) with portions of the structure being cut-away to moreclearly show the construction of the diaper 20 and with the portion ofthe diaper 20 which faces away from the wearer, the outer surface 52,facing the viewer. As shown in FIG. 1, the diaper 20 comprises acontainment assembly 22 preferably comprising a liquid pervious topsheet24, a liquid impervious backsheet 26 joined with the topsheet 24, and anabsorbent core 28 positioned between the topsheet 24 and the backsheet26; elasticized side panels 30; elasticized leg cuffs 32; an elasticwaist feature 34; and a closure system comprising a dual tensionfastening system generally multiply designated as 36. The dual tensionfastening system 36 preferably comprises a primary fastening system 38and a waist closure system 40. The primary fastening system 38preferably comprises a pair of securement members 42 and a landingmember 44. The waist closure system 40 is shown in FIG. 1 to preferablycomprise a pair of first attachment components 46 and a secondattachment component 48. The diaper 20 also preferably comprises apositioning patch 50 located subjacent each first attachment component46.

The diaper 20 is shown in FIG. 1 to have an outer surface 52 (facing theviewer in FIG. 1), an inner surface 54 opposed to the outer surface 52,a first waist region 56, a second waist region 58 opposed to the firstwaist region 56, and a periphery 60 which is defined by the outer edgesof the diaper 20 in which the longitudinal edges are designated 62 andthe end edges are designated 64. (While the skilled artisan willrecognize that a diaper is usually described in terms of having a pairof waist regions and a crotch region between the waist regions; in thisapplication, for simplicity of terminology, the diaper 20 is describedas having only waist regions, each of the waist regions including aportion of the diaper which would typically be designated as part of thecrotch region). The inner surface 54 of the diaper 20 comprises thatportion of the diaper 20 which is positioned adjacent to the wearer'sbody during use (i.e., the inner surface 54 generally is formed by atleast a portion of the topsheet 24 and other components joined to thetopsheet 24). The outer surface 52 comprises that portion of the diaper20 which is positioned away from the wearer's body (i.e., the outersurface 52 generally is formed by at least a portion of the backsheet 26and other components joined to the backsheet 26). The first waist region56 and the second waist region 58 extend, respectively, from the endedges 64 of the periphery 60 to the lateral centerline 66 of the diaper20. The waist regions each comprise a central region 68 and a pair ofside panels which typically comprise the outer lateral portions of thewaist regions. The side panels positioned in the first waist region 56are designated 70 while the side panels in the second waist region 58are designated 72. (In the discussion that follows, unless otherwisenoted, the diaper 20 will comprise a pair of side panels in each waistregion. While it is not necessary that the pairs of side panels or eachside panel be identical, they are preferably mirror images one of theother.) In a preferred embodiment of the present invention, the sidepanels 72 positioned in the second waist region 58 are elasticallyextensible in the lateral direction (i.e., elasticized side panels 30).(The lateral direction (x direction or width) is defined as thedirection parallel to the lateral centerline 66 of the diaper 20; thelongitudinal direction (y direction or length) being defined as thedirection parallel to the longitudinal centerline 67; and the axialdirection (Z direction or thickness) being defined as the directionextending through the thickness of the diaper 20.)

FIG. 1 shows a preferred embodiment of the diaper 20 in which thetopsheet 24 and the backsheet 26 have length and width dimensionsgenerally larger than those of the absorbent core 28. The topsheet 24and the backsheet 26 extend beyond the edges of the absorbent core 28 tothereby form the periphery 60 of the diaper 20. The periphery 60 definesthe outer perimeter or, in other words, the edges of the diaper 20. Theperiphery 60 comprises the longitudinal edges 62 and the end edges 64.

FIG. 2 is a cross-sectional view of the diaper 20 taken along sectionline 2--2 of FIG. 1 in the first waist region 56. FIG. 2 shows theconstruction of the elasticized waistband 35 of the elastic waistfeature 34. The elasticized waistband 35 is shown in FIG. 2 in itscontracted or relaxed condition. The elasticized waistband 35 preferablycomprises a portion of the topsheet 24, a portion of the backsheet 26that has preferably been mechanically stretched, and a bi-laminatematerial comprising an elastomeric member 76 positioned between thetopsheet 24 and the backsheet 26 and a resilient member 77 positionedbetween the backsheet 26 and the elastomeric member 76. The elasticizedwaistband 35 is also provided with regions of securement 78 wherein thebacksheet 26 and the topsheet 24 are joined to the bi-laminate materialof the elastomeric member 76 and the resilient member 77. Since thetopsheet 24 and the backsheet 26 are gathered when the bi-laminatematerial is in its relaxed condition, regions of differential securementare provided which form pleats 80.

FIG. 3 is a fragmentary cross-sectional view of the diaper 20 takenalong line 3--3 of FIG. 1 and depicts a preferred elastic waist featureconstruction in the first waist region 56. The absorbent core 28 isgenerally shown in FIG. 3 and shows the waist edge 83 of the absorbentcore 28. The topsheet 24 and the backsheet 26 encase the absorbent core28 and extend longitudinally outwardly beyond the waist edge 83 of theabsorbent core 28 to form a waist flap 89 and the end edge 64. Theelastic waist feature 34 extends longitudinally outwardly from the waistedge 83 of the absorbent core 28 in at least the central region 68 andforms at least a portion of the end edge 64. The elastic waist feature34 comprises an interconnecting panel zone 130, a first flexural hingezone 132 joining the interconnecting panel zone 130 with the containmentassembly 22 adjacent the waist edge 83 of the absorbent core 28, anelasticized waistband 35, and a second flexural hinge zone 134 joiningthe elasticized waistband 35 with the interconnecting panel zone 130. Asshown in FIG. 3, the elasticized waistband 35 comprises a shaping panelzone 136; a waistline panel zone 138; and a predisposed, resilient,waistband flexural hinge zone 140 joining the shaping panel zone 136 andthe waistline panel zone 138. As shown in FIG. 3, the interconnectingpanel zone 130 comprises a portion of the topsheet 24 and the backsheet26 while the elasticized waistband 35 comprises a portion of thetopsheet 24 and the backsheet 26 and the bi-laminate material of theelastomeric member 76 and the resilient member 77.

FIG. 2B is a simplified, fragmentary, enlarged plan view of thedisposable diaper 20 in the first waist region 56 showing generally thevarious zones and elements of the elastic waist feature 34. Theabsorbent core 28 is generally shown and has the waist edge 83 and theside edges 82. The panel zones of the elastic waist feature 34 aregenerally represented by the shaded areas. The panel zones comprise theinterconnecting panel zone 130 and the elasticized waistband 35comprising the shaping panel zone 136 and the waistline panel zone 138.The flexural hinge zones are generally depicted by lines even thoughthey may comprise regions or zones which have some significant width soas to exhibit bending/flexure deformation. The flexural hinge zonescomprise the first flexural hinge zone 132, the second flexural hingezone 134, and the waistband flexural hinge zone 140. The closure systemis shown as comprising a pair of first attachment components 46longitudinally aligned with the elasticized waistband 35 so as tomaintain/create lateral tension through the elasticized waistband 35.The first attachment component 46 preferably comprises a separate patchof material, preferably a hook fastening material, joined to thebacksheet 26.

The containment assembly 22 of the diaper 20 is shown in FIG. 1 ascomprising the main body (chassis) of the diaper 20. The containmentassembly 22 comprises at least an absorbent core 28 and preferably anouter covering layer comprising the topsheet 24 and the backsheet 26.When the absorbent article comprises a separate holder and a liner, thecontainment assembly 22 generally comprises the holder and the liner(i.e., the containment assembly 22 comprises one or more layers ofmaterial to define the holder while the liner comprises an absorbentcomposite such as a topsheet, a backsheet, and an absorbent core.) Forunitary absorbent articles, the containment assembly 22 comprises themain structure of the diaper with other features added to form thecomposite diaper structure. Thus, the containment assembly 22 for thediaper 20 generally comprises the topsheet 24, the backsheet 26, and theabsorbent core 28.

The absorbent core 28 may be any absorbent means which is generallycompressible, conformable, non-irritating to the wearer's skin, andcapable of absorbing and retaining liquids such as urine and othercertain body exudates. As shown in FIG. 1, the absorbent core 28 has agarment surface 100, a body surface 101, side edges 82, and waist edges83,

The absorbent core 28 may be manufactured in a wide variety of sizes andshapes (e.g., rectangular, hourglass, "T"-shaped, asymmetric, etc,) andfrom a wide variety of liquid-absorbent materials commonly used indisposable diapers and other absorbent articles such as comminuted woodpulp which is generally referred to as airfelt. Examples of othersuitable absorbent materials include creped cellulose wadding, meltblownpolymers including coform, cross-linked cellulosic fibers, tissueincluding tissue wraps and tissue laminates, absorbent foams, absorbentsponges, superabsorbent polymers, absorbent gelling materials, or anyequivalent material or combinations of materials. The configuration andconstruction of the absorbent core may also be varied (e.g., theabsorbent core may have varying caliper zones, a hydrophilic gradient, asuperabsorbent gradient, or lower average density and lower averagebasis weight acquisition zones; or may comprise one or more layers orstructures). The total absorbent capacity of the absorbent core 28should, however, be compatible with the design loading and the intendeduse of the diaper 20. Further, the size and absorbent capacity of theabsorbent core 28 may be varied to accommodate wearers ranging frominfants through adults.

A preferred embodiment of the diaper 20 has an asymmetric, modifiedT-shaped, absorbent core 28 having ears 102 in the first waist region 56but a generally rectangular shape in the second waist region 58. Thisconfiguration allows wider elasticized side panels 30 in the secondwaist region 58. An exemplary absorbent structure for use as theabsorbent core 28 of the present invention that has achieved wideacceptance and commercial success is described in U.S. Pat. No.4,610,678 entitled "High-Density Absorbent Structures" issued to Weismanand Goldman on Sep. 9, 1986. U.S. Pat. No. 4,673,402 entitled "AbsorbentArticles With Dual-Layered Cores" issued to Weisman, Houghton, andGellert on Jun. 16, 1987; and U.S. Pat. No. 4,888,231 entitled"Absorbent Core Having A Dusting Layer" issued to Angstadt on Dec. 19,1989; also describe absorbent structures that are useful in the presentinvention. The absorbent core 28 is preferably the commerciallysuccessful absorbent member described in U.S. Pat. No. 4,834,735,entitled "High Density Absorbent Members Having Lower Density and LowerBasis Weight Acquisition Zones", issued to Alemany and Berg on May 30,1989. Each of these references are incorporated herein by reference.

The backsheet 26 is positioned adjacent the garment surface 100 of theabsorbent core 28 and is preferably joined thereto by attachment means(not shown) such as those well known in the art. For example, thebacksheet 26 may be secured to the absorbent core 28 by a uniformcontinuous layer of adhesive, a patterned layer of adhesive, or an arrayof separate lines, spirals, or spots of adhesive. Adhesives which havebeen found to be satisfactory are manufactured by Century Adhesives,Inc. of Columbus, Ohio and marketed as Century 5227; and by H. B. FullerCompany of St. Paul, Minn. and marketed as HL-1258. The attachment meanswill preferably comprise an open pattern network of filaments ofadhesive as is disclosed in U.S. Pat. No. 4,573,986 entitled "DisposableWaste-Containment Garment", which issued to Minetola and Tucker on Mar.4, 1986, and which is incorporated herein by reference. An exemplaryattachment means of an open pattern network of filaments comprisesseveral lines of adhesive filaments swirled into a spiral pattern suchas is illustrated by the apparatus and methods shown in U.S. Pat. No.3,911,173 issued to Sprague, Jr. on Oct. 7, 1975; U.S. Pat. No.4,785,996 issued to Ziecker, et al. on Nov. 22, 1978; and U.S. Pat. No.4,842,666 issued to Werenicz on Jun. 27, 1989. Each of these patents areIncorporated herein by reference. Alternatively, the attachment meansmay comprise heat bonds, pressure bonds, ultrasonic bonds, dynamicmechanical bonds, or any other suitable attachment means or combinationsof these attachment means as are known in the art.

The backsheet 26 is impervious to liquids (e.g., urine) and ispreferably manufactured from a thin plastic film, although otherflexible liquid impervious materials may also be used. As used herein,the term "flexible" refers to materials which are compliant and willreadily conform to the general shape and contours of the human body. Thebacksheet 26 prevents the exudates absorbed and contained in theabsorbent core 28 from wetting articles which contact the diaper 20 suchas bedsheets and undergarments. The backsheet 26 may thus comprise awoven or nonwoven material, polymeric films such as thermoplastic filmsof polyethylene or polypropylene, or composite materials such as afilm-coated nonwoven material. Preferably, the backsheet is athermoplastic film having a thickness of from about 0.012 mm (0.5 mil)to about 0.051 mm (2.0 mils).

In a preferred embodiment of the present invention, at least a portionof the backsheet 26 is subjected to mechanical stretching in order toprovide both a "zero strain" stretch laminate that forms the elasticizedside panels 30 and to prestrain the portion of the backsheet coincidingwith the elastic waist feature. Thus, the backsheet 26 is preferablyelongatable, most preferably drawable, but not necessarily elastomeric,so that the backsheet 26 will, upon mechanical stretching, be at leastto a degree permanently elongated such that it will not fully return toits original undistorted configuration. In preferred embodiments, thebacksheet can be subjected to mechanical stretching without unduerupturing or tearing. Thus, it is preferred that the backsheet 26 havean ultimate elongation to break of at least about 400% to about 700% inthe cross-machine direction as measured using a method consistent withASTM D-638. Thus, preferred polymeric films for use as the backsheetcontain a high content of linear low density polyethylene. Particularlypreferred materials for the backsheet include blends comprised of about45-90%. linear low density polyethylene and about 10-55% polypropylene.Exemplary films for use as the backsheet of the present invention aremanufactured by Tredegar Industries, Inc. of Terre Haute, Ind. under thedesignation RR8220 blend for blown films and RR547S blend for castfilms. The backsheet 26 is preferably embossed (typically, to a caliperof about 0.127 mm (5.5 mils)) and/or matte finished to provide a moreclothlike appearance. Further, the backsheet 26 may permit vapors toescape from the absorbent core 28 (i.e., breathable) while stillpreventing exudates from passing through the backsheet 26.

The size of the backsheet 26 is dictated by the size of the absorbentcore 28 and the exact diaper design selected. In a preferred embodiment,the backsheet 26 has a modified hourglass shape extending beyond theabsorbent core 28 a minimum distance of at least about 1.3 cm to about2.5 cm (about 0.5 to about 1.0 inch) around the entire diaper periphery60. Preferably, the backsheet 26 is much wider than the absorbent core28 in the second waist region 58 so that the side panels 72 in thesecond waist region 58 are generally wider in the lateral direction thanthe side panels 70 in the first waist region 56.

The topsheet 24 is positioned adjacent the body surface 101 of theabsorbent core 28 and is preferably joined thereto and to the backsheet26 by attachment means (not shown) such as those well known in the art.Suitable attachment means are described with respect to joining thebacksheet 26 to the absorbent core 28. As used herein, the term "joined"encompasses configurations whereby an element is directly secured to theother element by affixing the element directly to the other element, andconfigurations whereby the element is indirectly secured to the otherelement by affixing the element to Intermediate member(s) which in turnare affixed to the other element. In a preferred embodiment of thepresent invention, the topsheet 24 and the backsheet 26 are joineddirectly to each other in the diaper periphery 60 and are indirectlyjoined together by directly joining them to the absorbent core 28 by theattachment means (not shown).

The topsheet 24 is compliant, soft feeling, and non-irritating to thewearer's skin. Further, the topsheet 24 is liquid pervious permittingliquids (e.g., urine) to readily penetrate through its thickness. Asuitable topsheet may be manufactured from a wide range of materials,such as porous foams; reticulated foams; apertured plastic films; orwoven or nonwoven webs of natural fibers (e.g., wood or cotton fibers),synthetic fibers (e.g., polyester or polypropylene fibers), or acombination of natural and synthetic fibers. Preferably, the topsheet 24is made of a hydrophobic material to isolate the wearer's skin fromliquids contained in the absorbent core 28.

In a preferred embodiment of the present invention, at least a portionof the topsheet 24 is subjected to mechanical stretching in order toprovide a "zero strain" stretch laminate that forms the elasticized sidepanels 30. Thus, the topsheet 24 is preferably elongatable, mostpreferably drawable, but not necessarily elastomeric, so that thetopsheet 24 will, upon mechanical stretching, be at least to a degreepermanently elongated such that it will not fully return to its originalconfiguration. In preferred embodiments, the topsheet 24 can besubjected to mechanical stretching without undue rupturing or tearing ofthe topsheet. Thus, it is preferred that the topsheet 24 have a lowcross-machine direction (lateral direction) yield strength.

There are a number of manufacturing techniques which may be used tomanufacture the topsheet 24. For example, the topsheet 24 may be anonwoven web of fibers. When the topsheet comprises a nonwoven web, theweb may be spunbonded, carded, wet-laid, meltblown, hydroentangled,combinations of the above, or the like. A preferred topsheet is cardedand thermally bonded by means well known to those skilled in the fabricsart. A preferred topsheet comprises staple length polypropylene fibershaving a denier of about 2.2. As used herein, the term "staple lengthfibers" refers to those fibers having a length of at least about 15.9 mm(0.625 inches). Preferably, the topsheet has a basis weight from about18 to about 25 grams per square meter. A suitable topsheet ismanufactured by Veratec, Inc., a Division of International PaperCompany, of Walpole, Mass. under the designation P-8.

The diaper 20 preferably further comprises elasticized leg cuffs 32 forproviding improved containment of liquids and other body exudates. Eachelasticized leg cuff 32 may comprise several different embodiments forreducing the leakage of body exudates in the leg regions. (The leg cuffcan be and is sometimes also referred to as leg bands, side flaps,barrier cuffs, or elastic cuffs.) U.S. Pat. No. 3,860,003 entitled"Contractable Side Portions For a Disposable Diaper" issued to Buell onJan. 14, 1975, describes a disposable diaper which provides acontractible leg opening having a side flap and one or more elasticmembers to provide an elasticized leg cuff (gasketing cuff). U.S. Pat.No. 4,909,803 entitled "Disposable Absorbent Article Having ElasticizedFlaps" issued to Aziz and Blaney on Mar. 20, 1990, describes adisposable diaper having "stand-up" elasticized flaps (barrier cuffs) toimprove the containment of the leg regions. U.S. Pat. No. 4,695,278entitled "Absorbent Article Having Dual Cuffs" issued to Lawson on Sep.22, 1987, describes a disposable diaper having dual cuffs including agasketing cuff and a barrier cuff. U.S. Pat. No. 4,704,115 entitled"Disposable Waist Containment Garment" issued to Buell on Nov. 3, 1987,discloses a disposable diaper or incontinent garment havingside-edge-leakage-guard gutters configured to contain free liquidswithin the garment. Each of these patents are incorporated herein byreference. While each elasticized leg cuff 32 may be configured so as tobe similar to any of the leg bands, side flaps, barrier cuffs, orelastic cuffs described above, it is preferred that each elasticized legcuff 32 comprise at least an inner barrier cuff 84 comprising a barrierflap 85 and a spacing elastic member 86 such as described in theabove-referenced U.S. Pat. No. 4,909,803. In a preferred embodiment, theelasticized leg cuff 32 additionally comprises an elastic gasketing cuff104 with one or more elastic strands 105, positioned outboard of thebarrier cuff 84 such as described in the above-referenced U.S. Pat. No.4,695,278.

The diaper 20 further comprises an elastic waist feature 34 thatprovides improved fit and containment. The elastic waist feature 34 atleast extends longitudinally outwardly from at least one of the waistedges 83 of the absorbent core 28 in at least the central region 68 andgenerally forms at least a portion of the end edge 64 of the diaper 20.Thus, the elastic waist feature 34 comprises that portion of the diaperat least extending from the waist edge 83 of the absorbent core 28 tothe end edge 64 of the diaper 20 and is intended to be placed adjacentthe wearer's waist. Disposable diapers are generally constructed so asto have two elastic waist features, one positioned in the first waistregion and one positioned in the second waist region. While a disposablediaper of the present invention can be constructed with a single elasticwaist feature encircling the wearer, the discussion regarding theelastic waist feature will focus on diapers having a pair of elasticwaist features, at least one, and preferably both, being constructedaccording to the present invention. Further, while the elastic waistfeature or any of its constituent elements can comprise a separateelement affixed to the containment assembly 22 of the diaper 20, theelastic waist feature 34 will be described with respect to a preferredembodiment in which the elastic waist feature 34 is constructed as anextension of other elements of the diaper such as the backsheet 26 orthe topsheet 24, preferably both the backsheet 26 and the topsheet 24.

While the elastic waist feature 34 need only comprise an elasticizedwaistband and a flexural hinge zone joining the elasticized waistbandwith the containment assembly; as shown in FIG. 3, the elastic waistfeature 34 preferably comprises several additional zones. In particular,the elastic waist feature 34 comprises an interconnecting panel zone130, a first flexural hinge zone 132 joining the interconnecting panelzone 130 with the containment assembly 22 adjacent the waist edge 83 ofthe absorbent core 28, an elasticized waistband 35, and a secondflexural hinge zone 134 joining the elasticized waistband 35 with theinterconnecting panel zone 130. The interconnecting panel zone 130preferably provides a flexible link between the elasticized waistband 35and the containment assembly 22. The elasticized waistband 35 provides amember that maintains a defined area coverage, contacts the wearer'swaist, and is elastically extensible in at least the lateral directionso as to dynamically fit against the waist of the wearer and todynamically conform to the waist of the wearer so as to provide improvedfit. As shown in FIG. 3, the elasticized waistband 35 comprises ashaping panel zone 136; a waistline panel zone 138; and a predisposed,resilient, waistband flexural hinge zone 140 joining the shaping panelzone 136 and the waistline panel zone 138. As used herein, the term"zone" is used to denote an area or element of the elastic waist feature34. While a zone of the elastic waist feature 34 may be a distinct areaor element; typically, a zone of the elastic waist feature will overlapsomewhat with an adjacent zone(s). (For illustration purposes, the zonesare delineated with brackets in FIG. 3.)

The interconnecting panel zone 130 provides a link between theelasticized waistband 35 and the containment assembly 22 to allowrotations and translations of the elasticized waistband 35 so that theelasticized waistband may move in functional contacting position andconform with the waist of the wearer. The interconnecting panel zone 130is preferably flexible so that the interconnecting panel zone is free todeform randomly throughout its length and width so as to allow theelasticized waistband 35 to maintain contact with the waist of thewearer and to allow the absorbent core 28 to position itself duringwear. While the interconnecting panel zone 130 may have a significantedge compression stiffness; in a preferred embodiment, theinterconnecting panel zone is flexible such that the edge compressionstiffness of the interconnecting panel zone is preferably substantiallyless than the edge compression stiffness of both the shaping panel zone136 and the waistline panel zone 138. It is preferred that theinterconnecting panel zone 130 have an edge compression stiffness lessthan about 50 grams_(f), more preferably less than about 25 grams_(f).Typically, the edge compression stiffness of the interconnecting panelzone (comprising a portion of the topsheet 24 and a portion of thebacksheet 26 joined together) is less than about 10 grams_(f). Further,while the interconnecting panel zone 130 may be elastically extensiblein the longitudinal direction, the lateral direction, or in any otherdirection, the interconnecting panel zone is preferably longitudinallynonextensible to provide a fixed dimension length between theelasticized waistband 35 and the containment assembly 22. The length ofthe interconnecting panel zone 130 is preferably at least about 4.75 mm(about 3/16 inch), more preferably between about 6.25 mm (about 1/4inch) and about 12.5 mm (about 1/2 inch) for medium-sized diapers.

The interconnecting panel zone 130 may be constructed from a separatematerial flexurally joined to the containment assembly 22 and/or theelasticized waistband 35, or as an extension of other elements of thediaper 20. In a preferred embodiment as shown in FIG. 3, theinterconnecting panel zone 130 comprises a portion of both the topsheet24 and the backsheet 26 extending beyond the waist edge 83 of theabsorbent core 28. The backsheet 26 and the topsheet 24 are preferablyjoined to each other (joined together) by an attachment means (notshown) in the interconnecting panel zone 130 so that they perform as aunit rather than independently of each other. The attachment means forsecuring the topsheet 24 and the backsheet 26 to each other preferablycomprises an open pattern network of adhesive deposited in a spiral orlooping pattern, although other attachment means as describedhereinbefore may also be used.

The interconnecting panel zone 130 is flexurally joined with thecontainment assembly 22 and the shaping panel zone 136 by flexural hingezones (first flexural hinge zone 132 and second flexural hinge zone 134,respectively) so that the elasticized waistband 35 may translate and/orrotate in the axial direction (Z-direction). As used herein, the term"flexurally joined" means a joint between panel zones or a panel zoneand the containment assembly adapted to allow relative flexural bendingbetween the panel zones. (As discussed hereinafter, this flexuralbending is not necessarily such that the panel zones will return totheir previous configuration when the forces causing the flexuralbending are removed (i.e., they are not necessarily resilient).

A flexural hinge zone can be constructed in various ways. The flexuralhinge zone may comprise a zone of structural discontinuity between panelzones. The cross-sectional configuration of the panel zones may bevaried to allow flexural bending between the panel zones. For example,the materials making up the panel zones can be scored, compressed,embossed, creased, folded, bonded, reduced, cut, notched, slit, oreliminated to form an axis or axes of flexural bending. Typically, thesemethods will concentrate stresses/tensions to a particular line or axesthrough which flexural bending can occur. A line of reduced extension ora line of restraint may also be formed between zones to form a hingezone. As an alternative, the flexural hinge zone may comprise a zone ofmaterial discontinuity between the panel zones. For example, thematerials making up the panel zones may have a relative differentmodulus of bending or elasticity to provide an area or zone of differentflexural resistance (differential bending stiffness between the zones)which allows flexural bending between the panel zones.

As shown in FIG. 3, the second flexural hinge zone 134 joining theelasticized waistband 35 (shaping panel zone 136) with theinterconnecting panel zone 130 is formed at the zone where there is astructural discontinuity due to the elimination of the elastomericmember 76 and the resilient member 77 from the interconnecting panelzone 130. Thus, the second flexural hinge zone 134 is created adjacentthe bottom edge of the elastomeric member 76 and the resilient member77. The first flexural hinge zone 132 joining the interconnecting panelzone 130 with the containment assembly 22 is formed at the zone wherethere is a structural discontinuity due to the absence of the absorbentcore 28 from the interconnecting panel zone 130.

The elasticized waistband 35 is that portion or zone of the diaper 20which is intended to elastically expand and contract and to dynamicallyfit the wearer's waist. While the elasticized waistband 35 can comprisea separate element flexurally joined with the interconnecting panel zone130, the elasticized waistband 35 is preferably formed as an extensionof the topsheet 24 or the backsheet 26, and, most preferably, thetopsheet 24 and the backsheet 26. The elasticized waistband 35 ispreferably that portion of the elastic waist feature 34 extending fromthe second flexural hinge zone 134 to, preferably but not necessarily,the end edge 64 of the diaper 20. In a preferred embodiment shown inFIG. 3, the elasticized waistband 35 comprises a shaping panel zone 136;a waistline panel zone 138; and a predisposed, resilient, waistbandflexural hinge zone 140 joining the shaping panel zone 136 and thewaistline panel zone 138.

The shaping panel zone 136 is the portion of the elasticized waistband35 that is positioned between the waistband flexural hinge zone 140 andthe second flexural hinge zone 134. The shaping panel zone 136 thus willtypically define the "lower segment" of the elasticized waistband 35.The shaping panel zone 136 is elastically extensible in at least thelateral direction to allow dynamic expansion and contraction of theelasticized waistband during use, The shaping panel zone 136, as laterdiscussed, also preferably has a relatively significant edge compressionstiffness so that the shaping panel zone 136 will not rope, deform, orcompact in use and so that the shaping panel zone 136 will maintain itsshape to resist compression and buckling of the elasticized waistbandduring use,

The waistline panel zone 138 is the portion of the elasticized waistband35 that is positioned toward the end edge of the diaper from thewaistband flexural hinge zone 140. The waistline panel zone 138 thuswill generally define the "upper segment" of the elasticized waistband35. The waistline panel zone 138 will preferably form at least a portionof the end edge of the diaper 20. The waistline panel zone 138 isdesigned to snugly fit against the waist of the wearer and todynamically move, expand, and contract with the waist of the wearer. Thewaistline panel zone 138 is elastically extensible in at least thelateral direction.

The edge compression stiffness of the shaping panel zone 136 and thewaistline panel zone 138 determines the resistance generally of theelasticized waistband 35 to compression deformation and bending in eachzone. In a preferred embodiment of the present invention, the shapingpanel zone 136 has a substantial, predetermined, edge compressionstiffness to allow the shaping panel zone to resist compression andbending forces applied to it and to maintain the shape of theelasticized waistband when applied to the wearer. Also, the shapingpanel zone 136 preferably has an edge compression stiffness greater thanor equal to the edge compression stiffness of the waistline panel zone138. In a preferred embodiment of the present invent(on, since theshaping panel zone 136 and the waistline panel zone 138 are constructedof the same materials, the edge compression stiffness of the shapingpanel zone 136 is about equal to the edge compression stiffness of thewaistline panel zone 138. It has been found that the shaping panel zone136 preferably has an edge compression stiffness greater than about 100grams_(f), more preferably greater than about 115 grams_(f), mostpreferably greater than about 130 grams_(f). Typically, in preferredembodiments of the present invention, the edge compression stiffness ofthe shaping panel zone 136 is between about 130 and about 170 grams_(f).The edge compression stiffness of a panel zone of the elastic waistfeature 34 can be determined using the method as hereinafter described.

The waistline panel zone 138 is resiliently/flexurally joined with theshaping panel zone 136 by the waistband flexural hinge zone 140. As usedherein, the term "resiliently/flexurally joined" means a joint betweenpanel zones or a panel zone and the containment assembly adapted toallow relative flexural bending between the panel zones when forces areapplied that provides a restoring force/moment to resiliently return thepanel zones to essentially their preceding configuration when the forcesare removed, This restoring force/moment is important in the functioningof the elasticized waistband 35 so that the shaping panel zone 136 andthe waistline panel zone 138 will assume their preceding in-use(pretensioned) configuration so that the elasticized waistbanddynamically follows the waist of the wearer with little slippingrelative to the wearer during the entire time of wearing, and does notallow the elasticized waistband to disfunctionally crumple or foldoverin a manner that alters its intended functionality during use.

The waistband flexural hinge zone 140 is resilient to allow flexuralbending between the shaping panel zone 136 and the waistline panel zone138 when forces generated by the waist of the wearer during use areapplied and to return the shaping panel zone 136 and the waistline panelzone 138 to essentially their preceding in-use (pretensioned)configuration when these forces are removed by providing a restoringforce/moment. In a preferred embodiment shown in FIGS. 1-3, thewaistband flexural hinge zone 140 is constructed to be resilient byproviding a resilient member 77 in the elasticized waistband 35. It hasbeen found that in order to provide the necessary resiliency for thewaistband flexural hinge zone and to overcome the normal forcesencountered during wear of the diaper so as to reduce rollover orroll-in, the waistband flexural hinge zone 140 should have a bendingflexure restoring force greater than about 20 grams_(f), more preferablygreater than about 25 grams_(f), and most preferably greater than about30 grams_(f). In preferred embodiments of the present invention, thewaistband flexural hinge zone will have a bending flexure restoringforce between about 30 grams_(f) and about 50 grams_(f). A method formeasuring the bending flexure restoring force of a flexural hinge zone,particularly the waistband flexural hinge zone, is hereinafterdescribed.

The waistband flexural hinge zone 140 is also "predisposed" so that thewaistline panel zone 138 and the shaping panel zone 136 will flexurallybend at a defined zone or axes in the elasticized waistband 35 for eachgiven application of force to the elasticized waistband 35. Thispredisposition of the waistband flexural hinge zone 140 also allows theelasticized waistband to flexurally deflect and follow the waist of thewearer without creasing or destroying the flexural rigidity of thematerials making up the elasticized waistband. Thus, a "predisposed"waistband flexural hinge zone will reduce the tendency for theelasticized waistband to bend or fold at random zones or axes duringuse. The "predisposed" waistband flexural hinge zone is defined by themanufacturer of the diaper to ensure flexural bending deflection at thedefined hinge zone. The formation of the waistband flexural hinge zone140 itself typically predisposes the axes or zone of flexural bendingwithin the elasticized waistband 35. As previously discussed, a flexuralhinge zone may comprise a zone of structural discontinuity or zone ofmaterial discontinuity. These zones of discontinuity will define theaxis of flexural bending. As an example, the waistband flexural hingezone 140 may comprise an axes or line created by embossing, creasing, orfolding the elasticized waistband along a defined line. For instance,the elasticized waistband could be prefolded by the manufacturer insideof the packaging for the article to preshape or preform a waistbandflexural hinge zone in the elasticized waistband. A line of reducedextension (or the reverse of a line being extensible and the surroundingareas being nonextensible) may be provided to form the waistbandflexural hinge zone by providing spaced apart bands or lines of glue,thread, or other materials that provide a structural discontinuitybetween them in order to predispose the waistband flexural hinge zone. Achange on the lamination or bonding pattern or technique may also formthe waistband flexural hinge zone. Any of the other ways of creating aflexural hinge zone previously discussed herein may also be used to formthe waistband flexural hinge zone.

In a preferred embodiment as shown in FIGS. 1 and 2B, the waistbandflexural hinge zone 140 is formed by a structural discontinuity betweenthe shaping panel zone 136 and the waistline panel zone 138. As shown inFIG. 2B, the materials forming the elasticized waistband 35 are securedto each other at transverse regions of securement 78 preferablycomprising a pattern of discrete, spaced, securement zones 79, mostpreferably the securement zones comprising dynamic mechanical bonds. Dueto the combined effect of the bonding pattern and the formation ofpleats in the waistband, the elasticized waistband 35 will tend to morereadily flexurally bend along the region in the pattern where there arefewer bonds. Thus, the pattern for the dynamic mechanical bonds, asshown in FIG. 2B, is designed as longitudinally staggered butoverlapping tows such that a lateral line moved longitudinally along theelasticized waistband will encounter the bonds except at the desiredlocation of the waistband flexural hinge zone. Thus, the waistbandflexural hinge zone 140 preferably comprises (is formed by) adiscontinuity in the pattern of the spacing of the securement zones 79.

The elasticized waistband 35 may be constructed in a number of differentconfigurations including those described herein with regard to formingan elasticized side panel. In a preferred embodiment as shown in FIG. 2,the elasticized waistband 35 preferably is constructed from fourmaterials laminated together.

The elasticized waistband 35 preferably comprises a portion of thetopsheet 24; a portion of the backsheet 26, this portion of thebacksheet being preferably "mechanically prestrained"; an elastomericmember 76; and a resilient member 77. The elastomeric member 76 and theresilient member 77 are preferably joined together, preferably bydynamic mechanical bonds, to form an elastic laminate prior to beingcombined with the topsheet 24 and the backsheet 26. This bi-laminate ispreferably positioned between the topsheet 24 and the backsheet 26 withthe resilient member 77 disposed toward the backsheet 26 and theelastomeric member 76 disposed toward the topsheet 24. Thus, theelastomeric member 76 is preferably positioned between the topsheet 24and the prestrained backsheet 26 with the resilient member 77 preferablybeing positioned between the prestrained backsheet 26 and theelastomeric member 76.

The elastomeric member 76 is operatively associated with the elasticizedwaistband 35, preferably between the topsheet 24 and the backsheet 26,so that the elastomeric member 76 allows the elasticized waistband 35 tobe elastically extensible in the lateral direction (i.e., laterallyelastically extensible), and so that it can contractively return to itssubstantially unrestrained configuration. The elastomeric member 76 canbe operatively associated in the elasticized waistband 35 in a number ofdifferent ways. As an example, the elastomeric member may be operativelyassociated in an elastically contractible condition so that theelastomeric member gathers or contracts the elasticized waistband. (Amore detailed description of the manner in which elastomeric materialsmay be secured in an absorbent article in an elastically contractiblecondition can be found in U.S. Pat. No. 3,860,003 issued to Buell onJan. 14, 1975, and in U.S. Pat. No. 4,081,301 issued to Buell on Mar.28, 1978; both patents being incorporated herein by reference.) Forexample, the elastomeric members 76 can be contractibly affixed in theelasticized waistband 35 by laterally extending the elastomeric member76, affixing the elastomeric member 76 to either or both the topsheet 24and the backsheet 26, and allowing the elastomeric member 76 to assumeits relaxed or contracted orientation.

Alternatively, the elastomeric member 76 can be operatively associatedin the elasticized waistband 35 by securing the elastomeric member 76 tothe topsheet 24, the backsheet 26, or both while the elastomeric member76 is in a substantially untensioned condition, at least a portion ofthe laminate containing the elastomeric member 76 then being subjectedto mechanical stretching sufficient to permanently elongate the topsheet24 and the backsheet 26 components of the laminate, and then thecomposite or elastomeric laminate is returned to its substantiallyuntensioned condition. The elasticized waistband 35 is thus formed intoa "zero strain" stretch laminate. (As discussed hereinafter, theelastomeric laminate may alternatively be operatively associated in atensioned condition and subjected to mechanical stretching to form amechanically stretched, pretensioned, stretch laminate.)

In an especially preferred embodiment as shown in FIG. 2, theelastomeric member 76 can be operatively associated in an uncontractedstate and then treated to contract. In this embodiment, the elastomericmember 76 can be formed from materials which contract unidirectionallyand become elastic following specific treatment such as heating.Examples of such materials are disclosed in U.S. Pat. No. 3,819,401issued to Massengale, et al. on Jun. 25, 1974 and in U.S. Pat. No.3,912,565 issued to Koch, et al. on Oct. 14, 1975. A more detaileddescription of a manner for using a heat-shrinkable elastomeric memberis described in U.S. Pat. No. 4,515,595 issued to Kievit and Osterhageon May 7, 1985; this patent being incorporated herein by reference.Typically, the topsheet 24, the backsheet 26, the elastomeric member 76,and any other components are secured together while in an uncontractedcondition. The laminate is then heated (as with heated air) and theelastomeric member 76 is allowed to return to its relaxed or contractedorientation.

The elastomeric members useful in the present invention may take on anumber of different sizes, shapes, configurations, and materials. Forexample, the elasticized waistband may be formed from one or a pluralityof elastomeric members operatively associated between the topsheet andthe backsheet; the elastomeric member may have varying widths andlengths; or the elastomeric member may comprise relatively narrowstrands of elastomeric material or a larger area patch of elastomericmaterial. One elastomeric material which has been found to be suitablefor use as the elastomeric member is an elastomeric foam such as thepolyurethane foam such as is available from Bridgestone of Yokahama,Japan and designated Bridgestone SG Polyurethane Foam. Other suitableelastomeric materials for use as the elastomeric member include "live"synthetic or natural rubber, elastomeric films (includingheat-shrinkable elastomeric films), formed elastomeric scrim, or thelike. In an especially preferred embodiment as is shown in FIG. 2, theelastomeric member 76 comprises a heat-shrinkable elastomeric film suchas marketed by Exxon Chemical Company of Florham Park, N.J.

The resilient member 77 is a layer or layers that provides enhancedshape recovery and bending stiffness to the elasticized waistband 35.The resilient member 77 provides compression/buckling resistance in thelongitudinal direction (machine direction) so that the waistbandflexural hinge zone 140 will be resilient so as to provide a restoringforce/moment. The resilient member 77 also has a relatively high caliperto provide a Z-direction bulk so as to somewhat fill the pleats 80 orrugosities of the elasticized waistband 35 so as to optimize itsresiliency. The resilient member 77 is also preferably hydrophobic toprevent wicking of liquids out of the elasticized waistband 35. In anespecially preferred embodiment, the resilient member 77 comprises anonwoven material in which the fibers are oriented in the machinedirection (longitudinal direction of the diaper) to reduce cross machinedirection (lateral) gather resistance so that the heat shrinkableelastomeric member can readily contract and to enhance the compressionresistance about a defined axes of bending, the waistband flexural hingezone 140.

While the resilient member 77 is preferably positioned between theelastomeric member 76 and the backsheet 26 as shown in FIG. 3, theresilient member 77 may alternatively be positioned between the topsheet24 and the elastomeric member 76, on the outside of the backsheet 26, onthe outside of the topsheet 24, or in a number of other configurations.The resilient member 77 is preferably positioned between the backsheet26 and the elastomeric member 76 to provide greater compression/bucklingresistance on the backsheet side of the elasticized waistband 35 sinceit will fill the rugosities or pleats 80 in the longitudinal axisbetween the bond sites, for providing bending resistance about thelateral axis of the elasticized waistband, and to optimize and reducewicking in the laminate material forming the elasticized waistband.

The resilient member 77 may take on a number of different sizes, shapes,configurations, and materials. For example, the resilient member may beformed from one or a plurality of resilient members; the resilientmember may have varying widths, lengths, thickness, and shapes. Theresilient member 77 preferably comprises a separate piece of materialpositioned in the elasticized waistband. Alternatively, the resilientmember may comprise a portion of any or all of the materials making upthe elasticized waistband 35, including the elastomeric member 76, thetopsheet 24, or the backsheet 26. In a particular alternativeembodiment, the resilient member 77 comprises the same piece as theelastomeric member 76, the elastomeric member 76 comprising a relativelythick elastomeric foam.

Suitable materials for use as the resilient member 77 of the elasticizedwaistband 35 of the present invention include woven webs; nonwoven webs;foams; laminate materials including film laminates of nonwoven laminatesof two or more nonwoven layers; scrims; corrugated materials thatprovide stiffness in at least one direction; and any combination of theabove materials or other materials as are known in the art.

Particularly preferred materials for the resilient member 77 comprisenonwoven webs that are hydrophobic and that have a drapability (asmeasured using ASTM B1388-64) of at least about 4 cm in the crossmachine direction and at least about 12 cm in the machine direction. Anexemplary material comprises a hydrophobic, nonwoven carded web having abasis weight in the range of from about 20-45 grams per square yard. Thefibers are oriented in the machine direction to provide enhancedbuckling/compression resistance in this direction. The nonwoven web iscomprised of 3 denier bicomponent fibers of polyester core material andcopolyolefin sheathing material, such fibers being available from Hoechtas CELBOND stable fibers; or of a polypropylene core material andpolyethylene sheathing material, such fibers being available fromDanaklon or Hercules. After carding the nonwoven web to orient thefibers in the machine direction, the nonwoven web is put through anair-thru bonding process to provide bulk (loft or thickness) to theresilient member to enhance its resiliency. (Examples of high loftnonwoven webs of bicomponent themoplastic resin fibers that are air-thrubonded are disclosed in U.S. Pat. No. 4,883,707 issued to Newkirk onNov. 28, 1989, and incorporated herein by reference.) Exemplary air-thrubonded nonwoven carded webs of bicomponent thermoplastic fibers areavailable from Fiberweb North America of Greenville, N.C. or fromVeratec Corporation of Walpole, Mass.

In a preferred embodiment of the present invention as shown in FIG. 2A,the portion of the backsheet 26 forming the elasticized waistband 35 hasbeen "prestrained" or "mechanically prestrained" (i.e., subjected tosome degree of localized pattern mechanical stretching to permanentlyelongate those portions of the backsheet forming the elasticizedwaistband 35). A prestrained backsheet improves not only the extensionof the elastomeric member 76 but also the heat-shrink contraction of thepreferred elastomeric members 76. In a preferred embodiment as shown inFIG. 2A, the prestrained backsheet assumes a pattern of ribs 142(strained portions) and unstrained gaps 144 between each rib 142 andbetween each row of ribs. This pattern is determined by the method andapparatus used to prestrain the backsheet. In this preferred embodiment,the ribs are 0.25 inch (about 6 mm) long, 0.030 inch (about 0.75 mm)wide, have a depth of 0.125 inch (about 3 mm), with a spacing betweeneach rib (gap) of 0.100 inch (about 2.5 mm). The area of the backsheetthat is prestrained is preferably about 5.5 inches (about 140 mm) wideby about 1 inch (about 25 mm) in length.

The backsheet 26 of the present invention can be prestrained bydirecting the backsheet through an incremental mechanical stretchingsystem similar to the operation described herein with respect to theformation of the "zero strain" stretch laminate elasticized side panels30, prior to combining the backsheet into the finished diaper product.The corrugated or grooved segments contained on the rolls areinterrupted to bring about the pattern of ribs in the machine directionand the cross-machine direction. The registration of the web of thebacksheet is such that the portion of the backsheet to be prestrainedsubstantially coincides with the corrugated or grooved segmentscontained on the uppermost corrugated rolls as the backsheet passesbetween the segments of the uppermost corrugated rolls and thecorrugated or grooved lowermost corrugated rolls. The backsheet canalternatively be prestrained by using deep embossing techniques as areknown in the art.

In a preferred method for making the diapers of the present invention,after the backsheet web has been prestrained, and after the backsheetweb has been removed from the corrugated combining rolls, a continuousspray glue is applied to the backsheet web. The elastic laminatecomprising the resilient member and the heat-shrinkable elastomericmember is dynamically mechanically bonded with the topsheet. Theresulting topsheet/elastomeric member/resilient member laminate is thenapplied to the prestrained backsheet web of the diaper and dynamicallymechanically bonded together to form the elasticized waistband 35. Thisdiaper web is then passed to a heat shrink apparatus to contract theheat shrinkable elastomeric member.

The elasticized waistband 35 further comprises transverse regions ofsecurement 78 shown in a generalized representation in FIG. 1 and inFIG. 2. A more detailed description of the transverse regions ofsecurement and alternative configurations for them are found in U.S.Pat. No. 4,515,595 issued to Kievit and Osterhage on May 7, 1985, andwhich patent is incorporated herein by reference. The transverse regionsof securement 78 extend essentially across the full width of theelasticized waistband 35, particularly the elastomeric member 76. Theterm "essentially across" is used in this context to indicate that thetransverse regions of securement need not extend absolutely across theentire width of the elastomeric member 76 so long as they extendsufficiently far across the width to provide the function discussedhereinafter. As illustrated, the transverse regions of securement 78 areshown to be disposed at essentially a right angle to the lateralcenterline 66 and to the lateral extent of the elasticized waistband 35.This is the preferred orientation. One can, however, depart from truetransversity without departing from the scope and spirit of theinvention.

In FIGS. 1 and 2B, the transverse regions of securement 78 are shown asdiscrete, spaced, securement zones 79 effectively attaching the webs ofmaterial forming the elasticized waistband 35 (the topsheet 24, thebacksheet 26, the resilient member 77, and the elastomeric member 76 ina preferred embodiment) together. While the shape of the discretesecurement zones may vary, the discrete securement zones 79 arepreferably circular, elliptical, oval, rectangular, or square shaped.The discrete securement zones 79 are preferably regularly spaced in apattern (as shown in FIG. 2B) (except where the waistband flexural hingezone 140 is formed), although they can be nonuniformly spaced. Theprecise means for providing the securement zones 79 can be readilyselected by those skilled in the art. Examples of such attachment meansinclude adhesive attachment, heat sealing, solvent sealing, autogeneousbonding, dynamic mechanical bonding, ultrasonic welding, and the like.Preferably, the transverse regions of securement 78 comprise oval(rounded rectangular) shaped discrete securement zones 79, preferablydynamic mechanical bonds, such as described in U.S. Pat. No. 4,919,738entitled "Dynamic Mechanical Bonding Method And Apparatus" which issuedto Ball, Goulait & Zorb on Apr. 24, 1990, and which patent isincorporated herein by reference, disposed in rows and columns with onecolumn missing or irregularly spaced to form the waistband flexuralhinge zone 140. The securement zones 79 are preferably from about 2.0 mm(about 0.078 in) by about 1.3 mm (about 0.52 in) and are preferablyspaced from about 7.0 mm (0.275 in) to about 8.9 mm (0.375 in) fromcenter to center in the transverse direction and from about 1.9 mm(0.375 in) to about 3.8 mm (0.15 in) from center to center in thelongitudinal direction. (One row of bond sites are eliminated in eachcolumn such that there is a longitudinal gap of about 1.0 mm (about0.040 in) to about 3.8 mm (0.150 in) from center to center to form thewaistband flexural hinge zone 140.) In the most preferred embodiment,the securement zones 79 are spaced about 8.3 mm (0.325 in) from centerto center in the transverse direction and about 2.8 mm (0.112 in) fromcenter to center in the longitudinal direction with an offset gapspacing of about 0.71 mm (0.028 in) from center to center betweenadjacent rows in the longitudinal direction.

As illustrated in FIG. 2, the discrete securement zones 79 on eitherside of the elastomeric member 76 are in register (i.e., they arecoextensive). This is a preferred orientation, but the discretesecurement zones 79 of the topsheet 24 to the elastic laminate materialcan be offset from the adjacent discrete securement zones 79 of thebacksheet 26 to the elastic laminate material.

In an alternative embodiment, the elasticized waistband in the secondwaist region 58 (or the first waist region 56 if elasticized side panelsare disposed therein) and the elasticized side panels 30 can be formedby securing a single piece of elastomeric material to the diaper 20 inboth the side panels 72 and the central region 68 of the second waistregion 58. Thus, the elasticized waistband 35 and the elasticized sidepanels 30 can be formed from the same piece of material to form aunitary structure. An example of such an elasticized waistband/sidepanel configuration is disclosed in the hereinbefore referenced U.S.Pat. No. 4,887,067 issued to Mood, et al. on Aug. 15, 1989, and whichpatent is incorporated herein by reference.

In a further alternative embodiment of the present invention, theelasticized waistband 35 may have differential extensibility along thelongitudinal axis when stretched in the lateral direction. Thedifferential extensibility of the elasticized waistband 35 allowsportions to laterally expand to a greater degree than other portionsalong the longitudinal axis. This differential extensibility of theelasticized waistband provides an abdominally compliant elasticizedwaistband, "expansive tummy panel", that allows the elasticizedwaistband to differentially shape, expand and move with the stomach ofthe wearer as the wearer moves, sits, and stands. Differentialextensibility along the longitudinal axis when stretched in the lateraldirection of the elasticized waistband can be achieved In a number ofways such as is discussed with respect to the elasticized side panels30. As shown in FIG. 6, a preferred differential extensibilityelasticized waistband has a pentagonal shape.

The diaper 20 is also preferably provided with a closure system(tensioning means) for dynamically creating/maintaining lateral tensionthrough the elasticized waistband 35. The lateral tension dynamicallycreated and maintained by the closure system "activates" the stretch ofthe elasticized waistband 35 thereby allowing it to more dynamicallyexpand and contract with the motions of the wearer. Gapping of theelasticized waistband is also reduced by the activated stretch since itis held in tension to snugly fit against the wearer's waist both whenthe diaper is initially fitted to the wearer and during use. Further,rollover of the elasticized waistband is reduced by the tensioncreated/maintained by the closure system. Thus, the closure systemimproves the fit and containment characteristics of the diaper.

While the closure system may take on a number of configurations such asadhesive tape tabs, mechanical closure tape tabs, fixed positionfasteners, or any other means for tensioning the elasticized waistbandas are known in the art; as shown in FIG. 1, the closure systempreferably comprises a waist closure system 40 comprising at least one,typically a pair of, first attachment components 46 and at least onesecond attachment component 48. More preferably, the closure systemadditionally comprises a primary fastening system 38 such that thediaper 20 has a dual tension fastening system 36. Preferred embodimentsof a diaper having a dual tension fastening system are described incommonly assigned, co-pending, U.S. patent application, P&G Case 4412,Weil et al., "Absorbent Article With Fastening System Providing DynamicElasticized Waistband Fit", filed concurrently herewith; thespecification and drawings of which are incorporated herein byreference.

The dual tension fastening system 36 forms both a side closure and awaist closure. The dual tension fastening system 36 thus comprises aprimary fastening system 38 for providing the side closure and a waistclosure system 40 for providing the first closure. The primary fasteningsystem 38 maintains the first waist region 56 and the second waistregion 58 in an overlapping configuration such that lateral tensions aremaintained around the circumference of the diaper to maintain the diaperon the wearer. The waist closure system 40 forms a waist closure thatdynamically maintains/creates lateral tensions through the elasticizedwaistband 35 so as to improve the fit and containment characteristics ofthe diaper 20 by reducing gapping, sagging, and rollover of theelasticized waistband 35.

As shown in FIG. 1, the primary fastening system 38 comprises asecurement member 42 disposed adjacent each longitudinal edge 62 in thesecond waist region 58, and at least one landing member 44 disposed inthe first waist region 56 so as to form a portion of the outer surface52. Each securement member 42 preferably comprises a tape tab 92 and afirst fastening component 112. The landing member 44 preferablycomprises a complementary second fastening component 114 engageable withthe first fastening component 112 of the securement member 42. Anexemplary primary fastening system wherein the first and secondfastening components each comprise mechanical closure elementscomprising hook and loop fastening materials is disclosed in U.S. Pat.No. 4,869,724 entitled "Mechanical Fastening Systems With Adhesive TapeDisposal Hearts For Disposable Absorbent Articles" issued to Scripps onSep. 26, 1989. Primary fastening systems utilizing mechanical closureelements are also disclosed in U.S. Pat. No. 4,846,815 entitled"Disposable Diaper Having An Improved Fastening Device" issued toScripps on Jul. 11, 1989; and U.S. Pat. No. 4,894,060 entitled"Disposable Diaper With Improved Hook Fastener Portion" issued toNestegard on Jan. 16, 1990. A primary fastening system havingcombination adhesive/mechanical closure elements is described in U.S.Pat. No. 4,946,527 entitled "Pressure-Sensitive Adhesive Fastener AndMethod of Making Same" issued to Battrell on Aug. 7, 1990. Each of thesepatents are incorporated herein by reference. In a preferred embodimentof the present invention as is shown in FIG. 1, the primary fasteningsystem 38 comprises an adhesive tape tab fastening system comprising atape tab 92 having an adhesive attachment layer 96 and a landing member44 comprising a reinforcing strip 116 joined to the backsheet 26.Examples of such adhesive tape tab fastening systems are disclosed inU.S. Pat. No. 3,848,594 entitled "Tape Fastening System for DisposableDiaper" issued to Buell on Nov. 19, 1974; and the adhesive tape tabs,reinforcing strip, and indicia means disclosed in U.S. Pat. No. B14,662,875 entitled "Absorbent Arttcle" issued to Hirotsu and Robertsonon May 5, 1987. Each of these patents are incorporated herein byreference.

Each securement member 42 of the primary fastening system 38 is intendedto provide a fastening means for engaging the landing member 44 so as toprovide a secure, preferably a variable positioning, side closure forthe diaper 20. Thus, the securement member 42 comprises at least onefastening component. Each securement member 42 also preferably comprisesa means for positioning the fastening component adjacent the landingmember 44 so as to achieve an optimum fitting side closure. Thus, thesecurement member 42 may comprise any of the well known configurationsand means for achieving a side closure on a diaper such as (i) a patchor strip of a fastening component disposed to form a portion of theinner surface of the diaper or (ii) a tape tab having a fasteningcomponent positioned thereon.

As shown in FIG. 1, each securement member 42 preferably comprises atape tab 92. Any of the well known configurations and constructions of atape tab may be used in the present invention. For example, an exemplarytape tab is described in detail in the hereinbefore referenced U.S. Pat.No. 3,848,594 issued to Buell on Nov. 19, 1974, and which patent isincorporated herein by reference. A particularly preferred tape tab 92has a fastening surface 98 and a backing surface 99. The fasteningsurface 98 is that surface of the tape tab 92 designed to engage thelanding member 44 of the present invention. Thus, the fastening surface98 of the tape tab 92 is generally oriented to face the inner surface 54of the diaper 20. The backing surface 99 is that surface opposed to thefastening surface 98 and generally faces the outer surface 52 of thediaper 20. The backing surface 99 is thus generally exposed during wearof the diaper 20.

The preferred tape tab 92 is one which is joined to the backsheet 26 ofthe diaper 20 to create a fixed portion 93 (i.e., that end of the tapetab 92 joined to the diaper 20 during manufacture). The tape tab 92 hasanother element which is the tab portion 94 (i.e., that end of the tapetab 92 that extends outwardly beyond the longitudinal edge 62 of thediaper 20 and that is grasped by the diaperer in securing the diaper onthe wearer). The distal edge 97 of the tape tab 92 preferably hasrounded corners to eliminate the possibility of harsh corner edgescontacting the wearer's skin so as to prevent stomach red marking. Thepreferred tape tab 92 of the present Invention also comprises a releaseportion 95 joined to the topsheet 24 of the diaper 20. The releaseportion 95 allows the tab portion 94 to be inwardly folded duringmanufacture to protect the adhesive attachment layer 96 fromcontamination or delamination prior to use. The release portion 95extends inwardly from the longitudinal edge 62 of the diaper 20preferably up to and juxtaposed over a portion of the elastic side panelmember 90 so that the load carried by the tape tab 92 is transferredinto the elastic side panel member 90 resulting in more effectivedistribution of the loads (wearing stresses). The tab portion 94 is alsopreferably shorter in the lateral direction (width) than the releaseportion 95 so that it is easter for the diaperer to initially grasp thetab portion 94.

The fastening component of the securement member 42 forms the closurebetween the securement member 42 and the complementary fasteningcomponent of the landing member 44. Thus, the fastening componentprovides a means for engaging the complementary fastening component ofthe landing member 44 to maintain the first waist region 56 and thesecond waist region 58 in an overlapping configuration to provide asecure side closure for the diaper 20. Further, it is preferred that adiaper fit a range of different size wearers and that the fasteningsystem be simple and easy to use. Therefore, the fastening componentsshould allow for variable positioning of the zone of closure so that thediaper may fit a range of sizes while also being simple to fasten withminimal effort. The fastening components thus comprise any of the wellknown attachment means for achieving an adjustable positioning secureclosure as defined hereinafter. Examples of such adjustable positioningattachment means include an adhesive attachment layer such as apressure-sensitive adhesive as are known in the art, a mechanicalclosure element such as a hook fastening material or a loop fasteningmaterial, any cohesive materials as are known in the art, or acombination of an adhesive/mechanical closure element, as hereinafterdescribed with respect to the waist closure system 40.

The fastening component is disposed on the securement member 42 suchthat it may be a separate member joined to and associated with thesecurement member 42 or a unitary member with the securement member 42.For example, the topsheet 24 or the backsheet 26 may be manufacturedfrom a material that mechanically engages the landing member 44 (thetopsheet 24 or the backsheet 26 being a unitary fastening component).Alternatively, a discrete patch or strip of material may be joined tothe securement member 42 (a separate fastening component). Preferably,the first fastening component 112 is a separate material, such as anadhesive attachment layer or a mechanical closure element, positioned onand joined to the tape tab 92. The first fastening component 112preferably comprises an adhesive attachment layer 96 coated on the tabportion 94 to form the fastening surface 98.

In addition, the first fastening component 112 may be positionedanywhere on the securement member 42. For example, the first fasteningcomponent 112 may be positioned in the side panels 72 of the secondwaist region 58 adjacent the longitudinal edges 62. (Exemplary examplesof this construction are shown in U.S. Pat. No. 4,610,682 issued to Koppon Sep. 9, 1986; and in U.S. Pat. No. 3,141,161 issued to Farris on Jul.21, 1964; each of which are incorporated herein by reference.) When thesecurement member 42 comprises a tape tab 92, the first fasteningcomponent 112 is preferably positioned either on all of or at least aportion of the fastening surface 98 of the tab portion 94. The firstfastening component 112 may comprise a combination adhesive/mechanicalclosure element having an adhesive attachment layer and a mechanicalclosure element disposed on another area of the tab portion 94 on thefastening surface 98 and adjacent the distal edge 97 of the tape tab 92.An exemplary embodiment of this configuration is disclosed in thehereinbefore referenced U.S. Pat. No. 4,869,724 entitled "MechanicalFastening Systems With Adhesive Tape Disposal Means For DisposableAbsorbent Article" issued to Scripps on Sep. 26, 1989, which isincorporated herein by reference.

The landing member 44 of the primary fastening system 38 provides ameans for securing itself to the securement member 42 to provide a sideclosure and to maintain the first waist region 56 and the second waistregion 58 in an overlapping configuration. The landing member 44 may bedisposed anywhere on the diaper 20 so long as it can engage thesecurement member 42 so as to provide the side closure and, preferably avariable positioning side closure. For example, the landing member 44may be disposed so as to form a portion of the outer surface 52 in thefirst waist region 56, so as to form a portion of the inner surface 54in the second waist region 58, or on any other portion or element of thediaper 20 which is disposed to engage the securement member 42. Becausethe landing member 44 determines the approximate location of where thesecurement member 42 should be placed for optimum fit, the landingmember 44 is preferably positioned so as to achieve variable positioningof the stale closure so that the diaper may fit a range of sizes, sothat an overlap between the first waist region 56 and the second waistregion 58 is achieved, and so that when the side closure is formed theattachment components of the waist closure system 40 engage each othersuch that the formation of the side closure also passively forms thewaist closure. The landing member 44 is preferably centered about thelongitudinal centerline 67 in the first waist region 56 and extendslaterally outwardly to almost the longitudinal edges 62.

The landing member 44 may either be a discrete, separate element orelements joined to the diaper 20 or a unitary piece of material with anelement of the diaper 20. The landing member 44 may thus comprise, forexample, the topsheet 24 or the backsheet 26. While the landing member44 can assume varying sizes and shapes, It preferably comprises one ormore patches of material joined to the backsheet 26 in the first waistregion 56 that allows for maximum fit adjustment of diaper 20 to thewearer. In a preferred embodiment of the diaper 20 as illustrated inFIG. 1, the landing member 44 has an elongate, rectangular-shape and issecured to the backsheet 26 in the central region 68 of the first waistregion 56 by an adhesive attachment means (not shown) as have beenpreviously discussed. The landing member 44 comprises a fasteningcomponent (second fastening component 114) engageable with the fasteningcomponent of the securement member 42 (first fastening component 112).Thus, the fastening component of the landing member 44 (second fasteningcomponent 114) may be manufactured from a wide range of materials andconfigurations capable of securely engaging the fastening component ofthe securement member 42 (first fastening component 112).

When the first fastening component 112 of the securement member 42comprises an adhesive attachment layer 96, the second fasteningcomponent 114 of the landing member 44 preferably comprises areinforcing strip 116 and/or the backsheet 26. When the first fasteningcomponent 112 of the securement member 42 comprises a mechanical closureelement, the second fastening component 114 also comprises a mechanicalclosure element. Thus, when the first fastening component 112 comprisesa hook fastening material, the second fastening component 114 preferablycomprises a loop fastening material.

In a preferred embodiment of the present invention as shown in FIG. 1,the landing member 44 preferably comprises a reinforcing strip 116releasably engageable with the adhesive attachment layer 96 of the tapetabs 92. The reinforcing strip 116 may comprise any of a number ofconfigurations and materials secured to the backsheet 26 of the diaper20. The reinforcing strip 116 is preferably a separate member secured tothe backsheet 26 to form a portion of the outer surface 52 of the diaper20. A preferred reinforcing strip 116 comprises a sheet of biaxiallyoriented polypropylene film.

The reinforcing strip 116 is also preferably provided with indicia means118 for aiding the diaperer in fitting the diaper to a wearer to obtainoptimal waist fit and leg opening fit. The indicia means 118 may be anytype of lines, patterns, ornamental designs, symbols, script, colorcodes, or other markings which have the capability, either inherently orwith additional denotation, to aid an individual fitting the diaper tothe wearer to promptly locate the desired affixation points for aparticular tape tab fastener. Such indicia means 118 are more fullydescribed in U.S. Pat. No. B1 4,662,875 entitled "Absorbent Article"which issued to Hirotsu and Robertson on May 5, 1987 and which isincorporated herein by reference. Indicia means of the present inventionare preferably a combination of different geometric shapes, colors, andobjects such as SESAME STREET or DISNEY characters,

The dual tension fastening system 36 additionally comprises a waistclosure system 40 for providing a waist closure adjacent the end edge 64of the diaper 20. The waist closure anchors a portion of the span of theend edge 64. Further, when the diaper 20 comprises an elasticizedwaistband 35, the waist closure dynamically creates/maintains lateraltensions through the elasticized waistband 35.

The waist closure anchors a portion of the span of the end edge 64 ofthe diaper 20, preferably a portion of the extensible span of theelasticized waistband 35. (i.e., The first and second attachmentcomponents of the waist closure system 40 act to anchor the positionalrelationship of the elasticized waistband 35 with the elasticized sidepanels 30.) The term "anchor" is used herein to mean that the attachmentcomponents provide an adjustable positioning fastener that achieves aclosure with sufficient shear resistance so that there is little or noshear slippage or movement between the attachment components once theclosure is achieved. The positional relationship of the elasticizedwaistband 35 with the elasticized side panels 30 (i.e., the geometricrelationship between the anchor zones of the first attachment components46) establishes a defined waist circumferential dimension adjacent theend edge 64 of the diaper 20 which is distinct (longitudinally spaced)from the circumferential dimension established by the side closureformed by the primary fastening system 38. This distinct, defined waistcircumferential dimension creates/maintains the required fitdimension(s) at the upper extremities (adjacent the end edge 64) of thediaper 20. Thus, the waist closure system 40 of the present inventioncan also be beneficial for use on diapers not employing an elasticizedwaistband (e.g., a waistshield or a nonextensible waist feature) so asto maintain a nonextensible fit at the end edge 64 (upper edge) of thediaper 20. The anchoring also provides a means for transferring shearforces (tensions) between the elasticized waistband 35 and theelasticized side panels 30 so as to enhance the initial pretensioncreated within the elasticized waistband 35.

The waist closure also creates/maintains lateral tension(s) through theelasticized waistband 35. The waist closure contributes some portion ofan initial pretension (lateral tension) within the elasticized waistband35 that allows the elasticized waistband 35 to snugly fit against thewearer's waist when initially fitted. The elasticized waistband 35maintains, during use, some portion of the pretension created within itby the waist closure. Since the elasticized waistband maintains someportion of the pretension created within it, the elasticized waistbandcan repeatedly elastically expand or contract with the motions of thewearer so as to snugly sustain the fit of the diaper against thewearer's waist throughout use. In particular, during wearing conditions,the elasticized waistband, in order to follow the movements of thewearer's waist, may have to contract to its untensioned state (i.e., thepretension goes to zero); however, because the attachment componentsremain engaged, the pretension will be reestablished within theelasticized waistband with further movement and activity by the wearer.(This is in contrast to most conventional elasticized waistbands thatare not pretensioned such as to not be able to further contract todynamically fit the wearer.) This initial pretensioning and maintenanceof the tension thus results in reduced gapping and better sustained fitof the elasticized waistband. Further, the lateral tension(s)created/maintained by the waist closure provide restoring forces withinthe elasticized waistband that reduce or counteract the incidence ofwaistband "rollover". Thus, the waist closure system 40 provides aclosure about the waist of the wearer to improve the initial and dynamicfit and containment characteristics of the diaper in the waist regions.

As shown in FIG. 1, the waist closure system 40 comprises at least one,preferably a pair of, first attachment component(s) 46 and at least onesecond attachment component 48. As shown in FIG. 1, the first attachmentcomponent(s) 46 are longitudinally aligned with the elasticizedwaistband 35 so that the lateral tensions dynamically created/maintainedby the waist closure system 40 extends in and through the elasticizedwaistband 35 during use. Further, the attachment components of the waistclosure system 40 are longitudinally spaced from the securement members42 and the landing member 44 of the primary fastening system 38 toprovide a distinct, defined waist circumferential dimension for thediaper and two distinct zones of lateral tension(s). The zone of tensioncreated by the primary fastening system 38 secures the garment on thewearer while the zone of tension dynamically created/maintained by thewaist closure system 40 dynamically maintains the upper waist closureduring wear. At least two anchor zones 122 are created by the attachmentcomponents when the waist closure is formed. These two anchor zones 122are laterally spaced from each other with all or at least a portion ofthe elasticized waistband 35 positioned between the anchor zones 122.The lateral spacing of these anchor zones can be achieved in a number ofdifferent ways. For example, the lateral spacing between the anchorzones 122 can be fixed by providing the waist closure system 40 with apair of first attachment components 46 laterally spaced from each otherand a second attachment component(s) 48 that allows adjustablepositioning with the first attachment components 46 (e.g., the secondattachment component(s) is relatively wide). In this embodiment, sincethe lateral spacing of the first attachment components 46 is fixed, thelateral spacing of the first attachment components 46 determines andsets the lateral spacing of the anchor zones. In an alternativeembodiment, the waist closure system 40 may comprise a pair of secondattachment components 48 laterally spaced from each other and a firstattachment component(s) 46 that allows adjustable positioning with thesecond attachment components 48 (e.g., the first attachment component 46is relatively wide). In this embodiment, the lateral spacing of theanchor zones is determined by the size of the waist of the wearer andthe overall dimension/shape of the diaper since the location of wherethe second attachment components 48 engage the first attachmentcomponent(s) 46 depends upon the overlap of the side panels in thesecond waist region 58 with the side panels in the first waist region56.

The preferred lateral spacing of the anchor zones 122 is designed toallow passive activation of the waist closure when the side closure isformed, and to assure the maintenance of normal forces applied to thewaist of the wearer to decrease the tendency of the elasticizedwaistband 35 to nonrecoverably rollover while providing an effectiveamount of stretch in the elasticized waistband that improves the fit andcontainment of the diaper In the waist. In order to maintain normalforces within the elasticized waistband that provide for recovery of thewaistband and minimize flipping out of the tensioned waistband (i.e.,nonrecoverable rollover), the lateral spacing of the anchor zones woulddesirably be kept to a minimum. However, in order to provide a maximumamount of stretch in the elasticized waistband, the lateral spacing ofthe anchor zones would be desirably chosen to be at a maximum.Therefore, the lateral spacing of the anchor zones is thus chosen so asto balance the need for maintaining the normal forces with the need forproviding an effective amount of stretch in the elasticized waistband.

In the diaper embodiment shown in FIG. 1 that is designed to fitmedium-size (5.4 kg to about 10.8 kg) babies, the lateral spacingbetween the anchor zones 122 (between the first attachment components46) is at least about 25 mm. More preferably, the lateral spacing is atleast about 50 mm. In the embodiment shown in FIG. 1, the lateralspacing of the first attachment components 46 is most preferably betweenabout 100 mm and about 200 mm. The lateral spacing of the anchor zones122 is determined by measuring the distance from the innermost line ofsecurement (i.e., that line closest to the longitudinal centerline 67)of one anchor zone to the innermost line of securement of the otheranchor zone with the elasticized waistband in is contracted state. Thus,in the embodiment illustrated in FIG. 1, the lateral spacing isdetermined by measuring the distance from the innermost edge of one ofthe first attachment components 46 to the innermost edge of the otherfirst attachment component 46.

Each attachment component comprises a fastening means that engages acomplementary fastening means for providing a variable positioning,passively activated, waist closure. As used herein, the term "variablepositioning" closure refers to a fastening system wherein at least oneof the positions of the components can widely vary so as to allow theuser to form a closure at a number of different locations. Thus, forexample, one of the components may have a fixed location on the diaper(e.g., the lateral spacing between the first attachment components 46 isfixed so as to provide for the pretensioning of the elasticizedwaistband 35 and the passive activation of the waist closure) while theother component allows for variable locations of attachment to the fixedcomponent. This is in contrast to a "fixed" positioning closure whichrequires both of the mating elements to be fixed in position such thatthe components must be joined at a specific location each time theclosure is formed (e.g., snaps and buckles). The waist closure system 40also provides a passively activated waist closure. By "passivelyactivated", it is meant that a functional waist closure is achieved withlittle or no additional effort by the diaperer after a suitable initialbody/leg fit (side closure) is achieved using the primary fasteningsystem 38. Passive activation of the waist closure system 40 requiresthe attachment components to not only engage each other so as to providea secure anchor with little or no additional effort but also to bepositioned on the diaper in an arrangement that creates/maintains thelateral tensions within the elasticized waistband 35.

As shown in FIG. 1, the attachment components preferably comprisemechanical closure elements. As used herein, the term "mechanicalclosure elements" describes fastening means which mechanically engageeach other for providing a variable-position closure. Thus, themechanical closure elements may comprise any of the well known means forachieving a variable-position closure by mechanical engagement such asVELCRO or other hook and loop fastening materials.

When the first attachment component 46 comprises a mechanical closureelement, the second attachment component 48 may comprise "identical"complementary mechanical closure elements or "distinct" complementarymechanical closure elements. As used herein, the term "identical"complementary mechanical closure elements is used to define mechanicalfastening systems wherein the engaging elements of the first componentand the second component comprise the same configuration or structurethat are interlocking. Examples of such systems are described in U.S.Pat. No. 4,322,875 entitled "Two Strip Materials Used For FormingFasteners" issued to Brown, et al. on Apr. 16, 1982. The term "distinct"complementary mechanical closure elements is used herein to definemechanical fastening systems wherein the first component is differentfrom the second component but is engageable therewith such as a hookfastening material and a loop fastening material. For example, if thesecond attachment component 48 comprises a loop fastening material thenthe first attachment component 46 will comprise a hook fasteningmaterial and vice versa.

As used herein, the term "hook fastening material" is used to designatea material having engaging elements. Thus, the hook fastening materialmay also be referred to is a male fastener. It should also be understoodthat the use of the term "hook" should be non-limiting in the sense thatthe engaging elements may comprise any shapes as are known in the art solong is they are adapted to engage a complementary mechanical closureelement such as a loop fastening material or another hook fasteningmaterial.

The hook fastening material is preferably intended to mechanicallyengage fibrous elements of a loop fastening material so as to provide asecure closure. Thus, a hook fastening material according to the presentinvention may be manufactured from a wide range of materials. Suitablematerials include nylon, polyester, polypropylene, or any combination ofthese materials, or other materials as are known in the art. A suitablehook fastening material comprises a number of shaped engaging elementsprojecting from a backing such as the commercially available materialdesignated "Scotchmate" brand No. FJ3402 available from Minnesota Miningand Manufacturing Company, St. Paul, Minn. Alternatively, the engagingelements may have any shape such as hooks, "T's", mushrooms, or anyother shape as are well known in the art. An exemplary hook fasteningmaterial is described in U.S. Pat. No. 4,846,815 entitled "DisposableDiaper Having An Improved Fastening Device" issued to Scripps on Jul.11, 1989, and which patent is incorporated herein by reference.

An especially preferred hook fastening material, as shown in FIG. 1,comprises an array of prongs 120 formed of thermoplastic material. Hotmelt adhesive thermoplastics, In particular polyester and polyamide hotmelt adhesives, are particularly well suited for forming the prongs ofthe hook fastening material. The prongs 120 are preferably manufacturedusing a modified gravure printing process by printing the thermoplasticmaterial in its molten state onto a substrate in discrete units,severing the material In a manner that allows stretching of a portion ofthe thermoplastic material prior to severance, and allowing thestretched molten material to "freeze" resulting in prongs. Thispreferred hook fastening material and methods and apparatus for makingsuch a hook fastening material are more fully detailed in EuropeanPatent Application 0 381 087; The Procter & Gamble Company; publishedAug. 8, 1990, which application is incorporated herein by reference.

A loop fastening material provides a plurality of fibrous elements thatengage the engaging elements of a hook fastening material. The loopfastening material may be manufactured from a wide range of materials toprovide fibrous elements, preferably loops. Such suitable materialsinclude nylon, polyester, polypropylene, any combination of thesematerials, or other materials as are known in the art. A suitable loopfastening material comprises a number of fiber loops projecting from abacking such as the commercially available material designated"Scotchmate" brand nylon woven loop No. SJ3401 available from MinnesotaMining and Manufacturing Company, St. Paul, Minn. Another commerciallyavailable loop fastening material comprises a tricot knit fabric havinga plurality of nylon filament loops projecting from a backing of nylonsuch as the commercially available material designated "Guilford No.16110" available from Guilford Mills of Greensboro, N.C. An exemplaryinexpensive loop fastening material and a method of making such a loopfastening material are described in European Patent Application 0 289198; The Procter & Gamble Company, published Nov. 2, 1988, whichapplication is incorporated herein by reference. A suitable loopfastening material may also be a woven or nonwoven fabric or any othertype of fibrous material or loop material which are well known in theart. Examples of nonwoven materials suitable for use as a loop fasteningmaterial herein are discussed with respect to the materials useful asthe topsheet 24 of the diaper 20. In a preferred embodiment, the loopfastening material is formed by the nonwoven material of the topsheet24.

The attachment components may alternatively comprise an adhesiveattachment layer (a layer of adhesive material). Adhesives useful in thepresent invention are preferably pressure-sensitive adhesives formulatedto adhere to a surface at ambient temperature by applying only lightpressure. Particularly preferred adhesives for use herein as theadhesive attachment layer are hot melt pressure-sensitive adhesives asare known in the art. An exemplary hot-melt pressure-sensitive adhesiveis a Kraton based adhesive with tacifiers and other additives such asmarketed by Findley Adhesives, Inc. of Elm Grove, Wis. under thetradename Findley 990 or H-2085,

The attachment components may further comprise a combinationadhesive/mechanical closure element. For example, the attachmentcomponents may comprise a combination fastener such as hook fasteningmaterial and an adhesive attachment layer juxtaposed with the hookfastening material or a mechanical closure element such as a hookfastening material having a layer of adhesive coated over a portion ofthe hook fastening material. An exemplary fastener having a combinationmechanical/adhesive system is the pressure-sensitive adhesive fastenerhaving a textured fastening surface such as is disclosed in U.S. Pat.No. 4,946,527 issued to Battrell on Aug. 7, 1990, which patent isincorporated herein by reference.

The attachment components may alternatively further comprise any othercohesive material or materials that are known in the art for providing avariable positioning fastener capable of being passively activated. Forexample, a cohesive strip or material can be foams, rubbers such ascrepe or latex rubbers, other adhesives, or a high static vinylmaterial. A separable fastener of a high static vinyl material is morefully described in U.S. Pat. No. 4,979,613 issued to McLaughlin &Kleinsmith on Dec. 25, 1990, which patent is Incorporated herein byreference.

The attachment components may comprise a separate element joined to thediaper 20 or may be a unitary element with one of the other componentsof the diaper. For example, the topsheet 24 may be manufactured from amaterial (e.g., a nonwoven web), that is capable of mechanicallyengaging the other attachment component (e.g., a hook fasteningmaterial). Further, the backsheet 26 can be formed from a web having atextured pattern with a layer of adhesive coated over a portion of thebacksheet surface to form a combination mechanical/adhesive fastener(attachment component) such as is shown in the hereinbefore referencedU.S. Pat. No. 4,946,527 to Battrell. In each of these cases, theattachment component is unitary with another component of the diaper.Alternatively, the attachment component may comprise a discrete strip orpatch joined to the diaper. In a preferred embodiment shown in FIG. 1,each first attachment component 46 comprises a discrete separate patchof a hook fastening material joined to the backsheet 26 so as to form aportion of the outer surface 52 while the second attachment component 48is a unitary element comprising a portion of the topsheet 24 in thesecond waist region 58.

In a particularly preferred embodiment of a medium sized diaper, such asthe diaper 20 shown in FIG. 1, the waist closure system 40 preferablycomprises a pair of first attachment components 46. Each firstattachment component 46 comprises an about 12 mm wide (i.e., generallyperpendicular to the longitudinal centerline 67) by about 19 mm patch ofa hook fastening material. The first attachment components 46 arepreferably positioned so as to have a lateral spacing of about 171 mm.Each first attachment component 46 is also spaced longitudinally fromthe end edge 64. If the longitudinal spacing of the first attachmentcomponent (measured from the end edge of the diaper to the closest edgeof the first attachment component) is too small, the first attachmentcomponent may be too high on the diaper and be in a position to contactthe wearer's skin; if the longitudinal spacing is too great, the firstattachment component may be so low as to allow some rollover of theelasticized waistband. The first attachment components are preferablyspaced from about 3 mm (1/8 inch) to about 15 mm (5/8 inch) from the endedge of the diaper, preferably about 6 mm (1/4 inch), The hook fasteningmaterial used for the first attachment components 46 preferablycomprises an array of thermoplastic prongs 120 formed on a backing; theprongs 120 of each hook fastening material most preferably beingoriented with the engaging means facing inward toward the longitudinalcenterline 67 of the diaper 20, The waist closure system 40 alsocomprises a single second attachment component 48 comprising a loopfastening material formed by a portion of the nonwoven material of thetopsheet 24.

The diaper 20 additionally comprises a positioning patch 50 locatedsubjacent the first attachment component 46, The positioning patch 50raises the first attachment component 46 in the Z direction (thickness)to allow the first attachment component 46 to come in better contactwith the second attachment component 48 and allow the waist closuresystem to more easily be closed (with less effort). Thus, the waistclosure system 40 is more effectively passively activated, Thepositioning patch 50 also provides a zone of increased flexuralstiffness that reduces the tendency of the flexible ear flaps 88 to foldover onto the first attachment component(s) 46 thereby occluding thehooks from being secured during diaper application. Thus, thepositioning patch 50 can comprise any element that provides a Zdirection build up to the first attachment components 46, As shown inFIG. 1, the positioning patches 50 each comprise a rectangular-shapedpiece of material positioned subjacent the first attachment component46. While the positioning patches 50 may be positioned directlysubjacent the first attachment components 46, the positioning patches 50are preferably positioned between the topsheet 24 and the backsheet 26.In order to provide a flexurally stiff circumference about the waist ofthe wearer, the lateral edges of the positioning patches can be abuttedto or slightly overlapped with the side edges 75 of the elasticwaistband member 76. The positioning patches 50 preferably comprise a 38mm wide by 32 mm long patch of elastomeric foam. More preferably, duringmanufacture of the diaper, the positioning patches 50 are formed of thesame material as the elastic side panel member 90 with the elastic sidepanel member 90 of one diaper and the positioning patch 50 of theadjacent diaper being formed from the same segment of material that isthen cut after the diaper (s completed. Thus, the positioning patch 50extends from the end edge 64 of the diaper 20 inward toward the centerof the diaper 20.

In a preferred embodiment, the diaper also comprises elasticized sidepanels 30 disposed in the second waist region 58. (As used herein, theterm "disposed" is used to mean that an element(s) of the diaper isformed (joined and positioned) in a particular place or position as aunitary structure with other elements of the diaper or as a separateelement joined to another element of the diaper.) The elasticized sidepanels 30 provide an elastically extensible feature that provides a morecomfortable and contouring fit by initially conformably fitting thediaper to the wearer and sustaining this fit throughout the time of wearwell past when the diaper has been loaded with exudates since theelasticized side panels allow the sides of the diaper to expand andcontract. Further, the elasticized side panels 30 develop and maintainwearing forces (tensions) that enhance the tensions developed andmaintained by both the primary fastening system 38 and the waist closuresystem 40 to maintain the diaper 20 on the wearer and enhance the waistfit. The elasticized side panels 30 especially assist in initiallypretensioning the elasticized waistband 35 since the diaperer typicallystretches the elasticized s(de panels 30 when applying the diaper 20 onthe wearer so that when the elasticized side panels 30 contract, tensionis transmitted from the elasticized side panels 30 through the waistclosure system 40 into the elasticized waistband 34. The elasticizedside panels 30 further provide more effective application of the diaper20 since even if the diaperer pulls one elasticized side panel 30farther than the other during application (asymmetrically), the diaper20 will "self-adjust" during wear. While the diaper 20 of the presentinvention preferably has the elasticized side panels 30 disposed in thesecond waist region 58; alternatively, the diaper 20 may be providedwith elasticized side panels 30 disposed in the first waist region 56 orin both the first waist region 56 and the second waist region 58.

While the elasticized side panels 30 may be constructed in a number ofconfigurations, an example of a diaper with elasticized side panelspositioned in the ears (ear flaps) of the diaper is disclosed in U.S.Pat. No. 4,857,067, entitled "Disposable Diaper Having Shirred Ears"issued to Wood, et al. on Aug. 15, 1989, which patent is incorporatedherein by reference. The elasticized side panels 30 may alternatively beformed in a number of other configurations. For example, U.S. Pat. No.4,381,781 issued to Sciaraffa, et al. on May 3, 1983, discloses a diaperhaving an elasticized waist in which an elastic member is positioned inan opening in both the topsheet and the backsheet of the diaper suchthat the stretch of the elastic member will not be constrained by thenon-elastic materials. While the Sciaffra et al. patent teaches thecriticality of removing both the topsheet and the backsheet portions ofthe diaper in those areas coinciding with the elastic member, thepresent inventors have learned that satisfactory elastic performance canalso be obtained when only one or when none of the coinciding portionsof the topsheet and the backsheet are removed, especially when theportions of the diaper web containing the elastic member are subjectedto an incremental mechanical stretching operation of the type describedhereinafter. A further embodiment of a diaper showing elasticized sidepanels is shown in U.S. Pat. No. 4,938,753 issued to Van Gompel, et al.on Jul. 3, 1990. This patent discloses a pant-like garment provided withstretchable side panels formed by attaching discrete stretchable membersto the side edges of the main body of the garment. Thus, the elasticizedside panels 30 of the present invention may comprise a separateelastically extensible material or laminate joined to the diaper. Asshown in FIG. 1, each elasticized side panel 30 preferably comprises anear flap 88 and an elastic side panel member 90 operatively associatedtherewith.

As shown in FIG. 1, each ear flap 88 comprises that portion of the sidepanel 72 that extends laterally outwardly from and along the side edge82 of the absorbent core 28 to the longitudinal edge 62 of the diaper20. The ear flap 88 generally extends longitudinally from the end edge64 of the diaper 20 to the portion of the longitudinal edge 62 of thediaper 20 that forms the leg opening (this segment of the longitudinaledge 62 being designated as leg edge 106). In a preferred embodiment ofthe present invention, each ear flap 88 in the second waist region 58 isformed by the portions of the topsheet 24 and the backsheet 26 thatextend beyond the side edge 82 of the absorbent core 28.

In a preferred embodiment of the present invention, the elastic sidepanel members 90 are operatively associated with the diaper 20 in theear flaps 88, preferably between the topsheet 24 and the backsheet 26,so that the elastic side panel members 90 allow the elasticized sidepanels 30 to be elastically extensible in the lateral direction(laterally elastically extensible). As used herein, the term"elastically extensible" means a segment or portion of the diaper thatwill elongate in at least one direction (preferably the lateraldirection for the side panels and the waistbands) when tensional forces(typically lateral tensional forces for the side panels and thewaistbands) are applied, and will return to about its previous size andconfiguration when the tensional forces are removed. Generally,elastomeric materials useful in the present Invention will contractivelyreturn to at least about 75% of their original configuration withinabout 5 seconds or less upon stretch and immediate release thereof(i.e., a "snappy" elastic).

The elastic side panel members 90 can be operatively associated in theear flaps 88 in a number of different ways. For example, the elasticside panel member 90 may be operatively associated in an elasticallycontractible condition so that the elastic side panel member 90 gathersor contracts the ear flap 88. (A more detailed description of a mannerin which elastomeric materials may be secured in an elasticallycontractible condition can be found in U.S. Pat. No. 3,860,003 issued toBuell on Jan. 14, 1975, and in U.S. Pat. No. 4,081,301 issued to Buellon Mar. 28, 1978; both patents being incorporated herein by reference.)For example, the elastic side panel members 90 can be contractiblyaffixed in the ear flap 88 by laterally extending the elastic side panelmember 90, joining the elastic side panel member 90 to either or boththe topsheet 24 and the backsheet 26, and allowing the elastic sidepanel member 90 to assume its relaxed or contracted orientation.

Alternatively, the elastic side panel member 90 can be operativelyassociated In an uncontracted state and then treated to contract. Forexample, the elastic side panel member 90 can be formed from materialswhich contract undirectionally and become elastic following specifictreatment such as heating. Examples of such materials are disclosed InU.S. Pat. No. 3,819,401 issued to Massengale, et al. on Jun. 25, 1974and in U.S. Pat. No. 3,912,565 issued to Koch, et al. on Oct. 14, 1975.A more detailed description of a manner for using a heat-shrinkableelastic member is described in U.S. Pat. No. 4,515,595 issued to Kievitand Osterhage on May 7, 1985; this patent being incorporated herein byreference. Typically, the topsheet, the backsheet, the elastic sidepanel member, and any other components are secured together while in anuncontracted condition. The laminate is then heated (as with heated air)and the elastic side panel member is allowed to return to tis relaxed orcontracted orientation.

In an especially preferred embodiment, the elastic side panel member 90is operatively associated in the ear flap 88 by joining the elastic sidepanel member 90 to the topsheet 24, the backsheet 26, or both while theelastic side panel member 90 is in a substantially untensionedcondition. At least a portion of the resultant composite elastomericlaminate containing the elastic side panel member 90 is then subjectedto mechanical stretching sufficient to permanently elongate the topsheetand the backsheet components (nonelastic components) of the laminate.The composite elastomeric laminate is then allowed to return to itssubstantially untensioned condition. The elasticized side panel is thusformed into a "zero strain" stretch laminate. (Alternatively, theelastic side panel member could be operatively associated in a tensionedcondition and then subjected to mechanical stretching; although this isnot as preferred as a "zero strain" stretch laminate.) As used herein,the term "zero strain" stretch laminate refers to a laminate comprisedof at least two plies of material which are secured to one another alongat least a portion of their coextensive surfaces while in asubstantially untensioned ("zero strain") condition; one of the pliescomprising a material which is stretchable and elastomeric (i.e., itwill return substantially to its untensioned dimensions after an appliedtensile force has been released) and a second ply which is elongatable(but not necessarily elastomeric) so that upon stretching the second plywill be, at least to a degree, permanently elongated so that uponrelease of the applied tensile forces, it will not fully return to itsoriginal undeformed configuration. The resulting "zero strain" stretchlaminate is thereby rendered elastically extensible, at least up to thepoint of initial stretching, in the direction of initial stretching.Examples of such "zero strain" stretch laminates are disclosed in U.S.Pat. No. 2,075,189 issued to Galligan, et al. on Mar. 30, 1937; U.S.Pat. No. 3,025,199 issued to Harwood on Mar. 13, 1962; U.S. Pat. No.4,107,364 issued to Sisson on Aug. 15, 1978; U.S. Pat. No. 4,209,563issued to Sisson on Jun. 24, 1980; and U.S. Pat. No. 4,834,741 issued toSabee on May 30, 1989. Each of these patents are incorporated herein byreference.

Particularly preferred methods and apparatus used for making "zerostrain" stretch laminates out of a topsheet, a backsheet, and anelastomeric member positioned between the same, use meshing corrugatedrolls to mechanically stretch the components. A discussion of suitableapparatus and methods for mechanically stretching portions of a diaperis contained in the hereinbefore referenced U.S. Pat. No. 4,107,364issued to Sisson on Aug. 15, 1978 and U.S. Pat. No. 4,834,741 issued toSabee on May 30, 1989. Particularly preferred apparatus and methods aredisclosed in co-pending, commonly assigned, U.S. patent application Ser.No. 07/662,536 entitled "Improved Method And Apparatus For IncrementallyStretching A Zero Strain Stretch Laminate Web To Impart ElasticityThereto"; P&G Case 4339; filed by Gerald M. Weber et al. on Feb. 28,1991; U.S. patent application Ser. No. 07/662,537 entitled "ImprovedMethod And Apparatus For Incrementally Stretching Zero Strain StretchLaminate Web In A Non-Uniform Manner To Impart A Varying Degree ofElasticity Thereto"; P&G Case 4340; filed by Kenneth B. Buell et al. onFeb. 28, 1991; and U.S. patent application Ser. No. 07/662,543 entitled"Improved Method And Apparatus For Sequentially Stretching Zero StrainStretch Laminate Web To Impart Elasticity Thereto Without Rupturing TheWeb"; P&G Case 4341; filed by Gerald M. Weber et al. on Feb. 28, 1991;the specifications and drawings of each one incorporated herein byreference.

Details of a particularly preferred incremental stretching system whichcan be employed in making "zero strain" stretch laminate elasticizedside panels of the present invention are set forth in FIG. 8. The fullyassembled diaper web 810 including the "zero strain" side panel web isdirected through the incremental stretching system.

Referring to FIG. 8, the timing of the diaper web 810 containing thesubstantially untensioned elastic side panel members (elastomericpatches 804) is such that the substantially untensioned elastomericpatches 804 substantially coincide with the corrugated or groovedsegments 824 contained on the uppermost corrugated rolls 825 as thediaper web 810 passes between the segments 824 of the uppermostcorrugated rolls 825 and the continuously corrugated or groovedlowermost corrugated rolls 821. In a preferred embodiment of the methodand apparatus, the grooved segments 824 are of greater overall lengththan the elastomeric patches 804, as measured in the machine direction,so as to impart a degree of extensibility to those portions of thetopsheet 24 and the backsheet 26 which are adjacent the elastomericpatches 804 in the diaper 20 (i.e., an extension panel 110 is formed).In addition, the grooved segments 824 preferably are not of sufficientlength to extend into the first waist region of the adjacent diaper,since it is preferable not to impart a degree of extensibility to theportion of the elastomeric patch 804 that will form the positioningpatch 50 of the adjacent diaper. While the exact configuration, spacingand depth of the complementary grooves on the uppermost and lowermostcorrugated rolls will vary, depending upon such factors as the amount ofelasticity desired in the "zero strain" stretch laminate portion, apeak-to-peak groove pitch of approximately 0.150 inches, an includedangle of approximately 12 degrees as measured at the peak, and apeak-to-valley groove depth of approximately 0.300 inches have beenemployed in a particularly preferred embodiment of the presentinvention. The exterior peak of each corrugation on the aforementionedcorrugated rolls typically exhibits a radius of approximately 0.010inches, while the internal groove formed between adjacent corrugationstypically exhibits a radius of approximately 0.040 inches. When thecorrugated rolls are adjusted so that their opposing peaks overlap oneanother to a depth between about 0.150 and about 0.175 inches, goodelastic characteristics have been produced in a laminate web of thepresent invention comprised of 80 mil thick elastomeric polyurethanefoam patches substantially continuously bonded on their opposed surfacesto a one mil thick polymeric backsheet and a nonwoven topsheet having abasis weight in the range of about 18 to 20 grams per square yard andcomprised of polypropylene fibers.

The degree of overlap of the opposing peaks on the aforementionedcorrugated rolls may of course be adjusted, as desired, to produce moreor less extensibility in the resultant "zero strain" stretch laminateweb. For the aforementioned roll geometry and laminate web construction,peak-to-peak overlap depths ranging from as little as about 0.050 inchesto as much as about 0.225 inches are feasible.

As can be seen from FIG. 8A, the diaper web 810 is caused by the idlerrolls 872, 874 to wrap the lowermost corrugated rolls 821 sufficientlyto cover the active vacuum ports 822 (shown in FIG. 8) locatedimmediately adjacent each continuous set of grooves 823 on the lowermostrolls 821. The vacuum ports 822, which are positioned so as tosubstantially coincide with the grooved segments 824 on the uppermostcorrugated rolls 825, are internally connected through the rolls 821 toa pair of vacuum manifolds 826 which exert suction against the diaperweb 810 as the diaper web is acted upon by the grooved segments 824 ofthe uppermost corrugated rolls 825.

To minimize the build up of either the adhesive used to secure theuntensioned elastomeric patches 804 to the topsheet web 806 and thebacksheet web 805 or the adhesive used to secure the coinciding portionsof the topsheet web and the backsheet web to one another, the groovedsegments 824 on the uppermost rolls 825 and the continuous grooves 823on the lowermost rolls 821 may be either comprised of a low frictionmaterial, such as TEFLON, or coated with a self-lubricating low frictionmaterial such as Permalon No. 503 spray coating, as available from MicroSurface Corporation of Morris, Ill.

The vacuum ports 822 on the lowermost rolls 821 are preferably coveredby a porous material, such as 0.090 inch mesh honeycomb 844, to providesupport to the portions of the diaper web 810 acted upon by the vacuumand to provide a good gripping surface against the web so as tosubstantially prevent lateral slippage or movement of the web across thehoneycomb surface whenever the web is acted upon by the vacuum.

Under optimum circumstances, the maximum degree of incrementalstretching which can be imparted to the "zero strain" portions of theside panel containing the elastomeric patches 804 is determined by thedepth of engagement between the grooves on segments 824 of the uppermostcorrugated rolls 825 and the continuous grooves 823 on the lowermostcorrugated rolls 821. However, it has been discovered that unless thestretch laminate web is substantially prevented from slipping orcontracting in a direction substantially parallel to the direction ofweb stretching as it passes between the meshing corrugated rolls, theoptimum degree of incremental stretching is not realized. Therefore, inits most preferred form, the incremental web stretching operation iscarried out while the outermost portions of all three layers comprisingthe "zero strain" stretch laminate are subjected to restraint, asgenerally shown in the cross-section of FIG. 8B, to substantiallyprevent the "zero strain" stretch laminate portions of the diaper webfrom slipping or contracting in a direction parallel to the desireddirection of stretching as it passes between the sets of sequentiallypositioned meshing corrugated rolls.

However, the present invention may also, if desired, be practiced toadvantage by restraining only the elongatable or drawable layer orlayers of the composite, i.e., it is not an absolute requirement thatthe outermost portions of the elastomeric patches also be restrainedduring the incremental stretching operation. In the latter instance, theelongatable or drawable layer or layers are still permanently elongatedduring the incremental stretching process, but the z-direction bulkingin the resultant "zero strain" stretch laminate web may be somewhat lesspronounced when the stretching tension is removed. This is due to thefact that the elastomeric patch undergoes a lesser degree of initialstretching during such a process. Accordingly, it can only undergo thissame amount of retraction when it returns to its undistortedconfiguration.

A "zero strain" stretch laminate embodiment of the aforementioned typemay also exhibit some degree of disproportionate localized straining inthe elongatable web or webs, particularly in the areas immediatelyadjacent the opposed edges of the elastomeric patches. In the case of anopaque polymeric backsheet web, these disproportionately strainedportions can become sufficiently thinned that they may even appeartransparent despite the fact that no rupture has taken place. In suchinstances the functionality, (e.g., the imperviousness) of the "zerostrain" stretch laminate portions of the diaper web is not impaired.Embodiments of the latter type are normally employed in situations wherethe aesthetic appearance of the "zero strain" stretch laminate portionsof the resultant diaper is either hidden from view by the design orconfiguration of the diaper or, if visible, is of no concern to the userof the diaper.

In still another embodiment of the present invention even rupture of oneor more of the elongatable nonelastic webs may not render the resultant"zero strain" stretch laminate web unacceptable for its intended purpose(e.g., rupture of the backsheet web does not necessarily destroy thelaminate web's functionality for its intended purpose as long as one ofthe other plies in the laminate web provides the desired function in thefinished article). For example, some degree of rupturing in theelongatable backsheet web will not destroy the imperviousness of theresultant diaper web if the elastomeric patches also comprise aliquid-impervious material). This is particularly true with respect tothose "zero strain" stretch laminate web embodiments employingsubstantially continuous bonding between the plies in question, sincerelatively close adherence of the plies to one another after incrementalstretching renders such ply damage difficult to detect by the end useror the diaperer.

Because the diaper web 810 shown in FIGS. 8-8B is substantiallyimpervious to the passage of air by virtue of the presence of theuppermost backsheet web 805, the vacuum ports 822 covered by the poroushoneycomb material 844 can, if desired, be employed immediately adjacenteach set of machine direction oriented grooves 823 in the lowermostcorrugated rolls 821. If the elastomeric patches 804 are sufficientlypervious to the passage of air, the suction forces generated by thevacuum will pass through the topsheet web 806 and the elastomericpatches 804 so as to tightly grip the overlying portions of thebacksheet 805. In this instance, all three layers comprising the "zerostrain" stretch laminate portions of the diaper web will be restrainedduring the incremental stretching operation.

If the elastomeric patches were not substantially pervious to thepassage of air, it would be necessary to either (a) position the vacuumports 822 and the overlying honeycomb material 844 just outside theopposed edges of the elastomeric patches 804 so that suction forcescould be exerted on the backsheet web 805 through the topsheet web 806;or (b) restrain all three layers comprising the "zero strain" stretchlaminate portions of the diaper web by means of suitable clampingapparatus capable of acting upon the opposed surfaces of the diaper web.

The suction forces applied to the diaper web 810 shown in FIGS. 8-8B bythe vacuum ports 822 acting through the porous honeycomb material 844substantially prevent those portions of the diaper web 810 containingthe substantially untensioned elastomeric patches 804 from slipping orcontracting in a laterally inward direction as they pass between themeshing portions of the continuous grooves 823 on the lowermostcorrugated rolls 821 and the grooved segments 824 on the uppermostcorrugated rolls 825.

Because the "zero strain" stretch laminate portions of the diaper web810 containing the elastomeric patches 804 are laterally restrainedthroughout the sequential web stretching operation, all portions of the"zero strain" stretch laminate web located intermediate the points ofrestraint are subject to substantially uniform incremental stretching asthe web passes between the continuous grooves 823 on the lowermostcorrugated rolls 821 and the meshing portions of the grooved segments824 on the uppermost corrugated rolls 825.

This not only maximizes the effectiveness of the incremental webstretching operation by forcing the elongatable topsheet and backsheetwebs secured to the elastomeric patches to undergo the fullest possibledegree of elongation during the stretching operation, but alsosubstantially prevents disproportionately high straining of the topsheetand/or backsheet webs to which they are secured in the areas immediatelyadjacent the opposed peripheral edge portions of the elastomericpatches.

FIG. 9 discloses an alternative incremental web stretching system whichcan be employed. In the incremental web stretching system shown in FIG.9, a pair of resilently compressible disks 940 are mounted adjacent eachside of the grooved segments 924 of the uppermost corrugated rolls 925.The compressible disks 940 are of a large enough diameter that theytightly grip the diaper web 910 and hold it securely against thecoinciding non-grooved portions of the lowermost corrugated rolls 921 asgenerally shown in the cross-section of FIG. 9A. Like the vacuum portsand the porous honeycomb material in the embodiment of FIG. 8, theclamping effect created by the compressible disks 940 and the coincidingnon-grooved portions of the lowermost rolls 921 substantially preventsthe portion of the diaper web 910 containing the elastomeric patches 904from contracting in a direction parallel to the direction of stretchingas the web passes between the meshing corrugated rolls, The FIG. 9embodiment can be used with equal facility on laminate structurescomprised of webs which are either pervious or impervious to the passageof air.

As will be appreciated by those skilled in the art, the foregoingrestraint methods may be employed either individually or in combinationwith one another to produce the benefits herein described in theresultant "zero strain" stretch laminate portions of the resultantdiaper web.

From the description contained herein, it is clear that the improvedmethod and apparatus may be employed to advantage to produce a widerange of diapers either comprised entirely of or including one or morediscrete, isolated "zero strain" stretch laminate web portions.

It is also recognized that while a pair of meshing corrugated rollshaving their corrugations aligned substantially parallel to one anotherare disclosed in the accompanying drawings, the present invention may bepracticed with equal facility employing pairs of corrugated rollswherein the corrugations are not all oriented parallel to one another.Furthermore, the corrugations on such pairs of corrugated rolls need notnecessarily be aligned parallel to either the machine or thecross-machine direction. For example, if a curvilinear waistband orlegband portion is desired in a single use diaper constructed using the"zero strain" stretch laminate technology herein disclosed, the meshingteeth on the pairs of corrugated rolls employed to incrementally stretchthe "zero strain" laminate web portions of the diaper web may be arrayedin the desired curvilinear configuration to produce elasticity along thedesired curvilinear contour rather than in a straight line.

It is further recognized that while the preferred processes hereindisclosed employ meshing cylindrical corrugated rolls, the web restraintprinciples may also be carried out utilizing an intermittent stampingoperation employing meshing platens to incrementally stretch the "zerostrain" stretch laminate portions of the web or article in question, inthe latter instance, the only requirement is that the portions of the"zero strain" stretch laminate web to be incrementally stretched beadequately restrained by suitable vacuum or clamping means before themeshing platens are able to exert enough force on the web to causeslippage or contraction in a direction parallel to the direction ofstretching.

The elastic side panel members 90 can be joined to either the topsheet24, the backsheet 26, or both using either in an intermittent bondingconfiguration or a substantially continuous bonding configuration. Asused herein, an "intermittently" bonded laminate web means a laminateweb wherein the plies are initially bonded to one another at discretespaced apart points or a laminate web wherein the plies aresubstantially unbonded to one another in discrete spaced apart areas.Conversely, a "substantially continuously" bonded laminate web means alaminate web wherein the plies are initially bonded substantiallycontinuously to one another throughout the areas of interface. Theintermittent bonding configuration is normally desirable for "zerostrain" laminate webs in those situations where the substantiallyinelastic webs in the laminate are relatively elongatable or drawablewithout rupture and where a high degree of z-direction bulking isdesired in the finished laminate. A continuous bonding configuration hasgenerally been found desirable for "zero strain" laminate webs where thedegree of z-direction bulking of the finished laminate is not of primeimportance and one or more of the relatively inelastic webs in thelaminate is difficult to elongate or draw without causing rupture. Inthe latter situation, a substantially continuous bonding configurationmaintains all of the layers of the laminate in relatively closeadherence to one another after the incremental stretching operation.Accordingly, even if one or more of the relatively inelastic webs isdamaged to the point of rupture during the incremental stretchingoperation, the relatively close adherence of the damaged portions of therelatively inelastic web or webs to the elastomeric ply makes itdifficult for the end user to perceive that any damage has occurred.Provided that the rupture of the relatively Inelastic web or webs doesnot defeat the web's intended functionality, (e.g., Imperviousness), thedamage which does occur to the relatively inelastic web or webs duringthe incremental stretching operation is generally not perceived as anegative in the end product.

Thus, an unexpected benefit which results from the use of a continuousbonding configuration in particularly preferred "zero strain" stretchlaminate webs is that it permits the manufacturer of the diaper toselect from a much wider range of relatively Inelastic webs which may besuccessfully employed in laminates of the present invention. In essence,it permits the use of relatively inelastic webs which would not normallybe considered drawable to any appreciable extent in "zero strain"stretch laminate webs of the present invention. Accordingly, unlessexpressly stated otherwise, the term "drawable" as used herein, is notintended to exclude relatively elastic webs which undergo a degree ofthinning or damage during the incremental stretching operation.

In a preferred embodiment of the present invention, the elastic sidepanel member 90 is substantially continuously bonded to both thetopsheet 24 and the backsheet 26 using an adhesive. A glue applicatormay be used to apply a substantially uniform and continuous layer ofadhesive to the backsheet 26 and/or the topsheet 24 in thosepredetermined areas where the substantially untensioned elastic sidepanel member 90 will be placed. In a particularly preferred embodiment,the adhesive selected is stretchable and the glue applicator comprises amelt blown applicating system.

One such melt blown adhesive applicating system which has been found tobe particularly well suited for producing a substantially continuouslybonded "zero strain" stretch laminate web is a melt blown sprayapplicator Model No. GM-50-2-1-GH, as available from J&H Laboratories ofGainesville, Ga. The latter system employs a nozzle having 20 orificesper lineal inch, as measured in the cross-machine direction, eachorifice measuring approximately 0.020 inches in diameter. A FindleyH-2176 Hot Melt Adhesive, as available from Findley Adhesives of ElmGrove, Wis. is preferably heated to a temperature of approximately 340°F. and applied to the backsheet and/or the topsheet at a rate ofapproximately 7.5-10 milligrams per square inch. Heated compressed airat a temperature of approximately 425° F. and a pressure ofapproximately 50 psig is issued through the secondary orifices in theadhesive nozzle to assist in uniformly distributing the adhesive fibrilsduring the laydown operation.

The intimate contact of the hot adhesive with the backsheet 26 for thetime which passes prior to the incremental stretching of the resultant"zero strain" stretch laminate portion of the diaper provides softeningof the backsheet 26. For some webs, such as conventional polyethylenebacksheet material, this softening has been found beneficial inminimizing damage to the backsheet during the incremental web stretchingprocess. This may be particularly important in situations where the webin question imparts some function, (e.g., impervious), to the diaper.

Alternatively, the elastic side panel member 90 and any other componentscomprising the "zero strain" portions of the diaper 20 may beintermittently or continuously bonded to one another using unheatedadhesive, heat bonding, pressure bonding, ultrasonic bonding, dynamicmechanical bonding, or any other method as is known in the art.

The elastic side panel members 90 may take on a number of differentsizes, shapes, configurations and materials. For example, theelasticized side panels 30 may be formed from one or a plurality ofelastic side panel members 90 operatively associated in each ear flap88; the elastic side panel members may have varying widths and lengths;or the elastic side panel members may comprise relatively narrow strandsof elastomeric material or a larger area elastomeric patch. Oneelastomeric material which has been found to be especially suitable foruse as the elastic side panel member 90 (especially for "zero strain"stretch laminates) is an elastomeric foam having an elongation to breakof at least about 400% and an extension force of about 200 grams perinch of sample width at 50% extension of its unstrained length.Exemplary elastomeric foams which have been found suitable for use as anelastic side panel member include: (a) crosslinked natural rubber foamspreferably having a caliper of approximately 50 mils and a density of13.3 pounds per cubic hot (0.214 g/cm³), such as is available fromFulflex Inc. of Middletown, R.I.; or as available from Ludlow CompositesCorporation of Fremont, Ohio and marketed under the tradename Baby Foam;or (b) polyurethane foams having a caliper of approximately 80 mils anda density of approximately 2.06 pounds per cubic hot (0.033 g/cm³) suchas is available from Bridgestone of Yokohama, Japan and marketed underthe tradename Bridgestone SG polyurethane foam; or as available fromGeneral Foam of Paramus, N.J. and marketed under the designation ofPolyurethane Foam No. 40310. Other suitable elastomeric materials foruse as the elastic side panel members 90 include "live" synthetic ornatural rubber, other synthetic or natural rubber foams, elastomericfilms (including heat shrinkable elastomeric films), elastomeric scrim,elastomeric woven or nonwoven webs, elastomeric composites such aselastomeric nonwoven laminates, or the like.

As shown in FIG. 1, the elastic side panel member 90 comprises a patchof elastomeric material (elastomeric patch) that preferably extendsthrough a majority of the length of the ear flap 88 in the second waistregion 58. When the diaper is manufactured, the elastomeric patch ispreferably positioned so that it forms not only the elastic side panelmember 90 of one diaper but also the positioning patch 50 in the firstwaist region 56 of the adjacent diaper. Thus, registry problems insecuring the elastic side panel members to the diaper at high speed,such as disclosed in the previously referenced wood, et al. patent, areeliminated. Thus, the elastic side panel member 90 preferably extendsfrom the end edge 64 of the diaper 20 inward toward the leg edge 106 ofthe ear flap 88. The length and width of the elastic side panel members90 are dictated by the diaper's functional design.

While the elastic side panel member 90 may longitudinally extend throughthe entire length of the ear flap 88, it is preferred that the elasticside panel member 90 extend through only a portion of the length of theear flap 88 so as to form an extension panel 110. As shown in FIG. 1,the extension panel 110, the portion of the elasticized side panellongitudinally extending from the base edge 108 of the elastic sidepanel member 90 to the leg edge 106 of the ear flap 88, has also beenmechanically stretched at least to a degree to be extensible (i.e., thematerials that make up the extension panel 110 have been prestrained orpermanently elongated), This "prestrained" extension panel allows thisportion of the elasticized side panel to effectively elongate (yield)when the "zero strain" stretch laminate portion of the elasticized sidepanel is extended, without generating excessive tension forces near theleg regions of the wearer that could cause skin irritation or redmarking in the legs. (i.e., Without the "prestrained" extension panel,tensional forces would be concentrated along a line through theextension panel 110 when the elasticized side panel is extended thatcould indent, rub, or chafe the skin of the wearer.) While there are anumber of ways to prestrain the extension panel 110 of the elasticizedside panels 30, the extension panel 110 is preferably prestrained in thesame manner as the mechanical stretching performed on the "zero strain"stretch laminate portion. While the extension panel 110 of theelasticized side panels 30 may be formed from a number of differentmaterials, in the preferred embodiment shown in FIG. 1, the extensionpanel 110 is formed from the portions of the topsheet 24 and thebacksheet 26 forming the ear flap 88,

It has been found that the extension characteristics Including theextension forces, extension modulus, and available stretch (extension);and the contractive forces; elastic creep; elastic hysteresis; and rateof contraction of the elasticized side panels 30 are Importantconsiderations in the performance of both the elasticized side panels 30and the diaper 20. The extension characteristics give the diaperer andwearer the overall perceived "stretchiness" during use. They also effectthe ability of the diaperer to achieve a suitable degree of applicationstretch (i.e., for a "normally" perceived tensioning of the diaperduring application, the total amount of resultant stretch is thatdesired to achieve/maintain good conformity of fit). An elasticized sidepanel with a relatively high extension modulus can cause red marking onthe wearer's skin while a relatively low extension modulus can causesagging/slipping on the wearer. Elasticized side panels having toolittle available stretch may not achieve a suitable level of bodyconformity and may contribute in making the diaper uncomfortable to wearand hard to don. A diaper having elasticized side panels with very lowcontractive forces, or poor elastic creep or elastic hysteresis may notstay in place on the wearer and may tend to sag/slip on the wearerresulting in poor fit and containment.

For the elasticized side panels 30 of the present invention, it has beenfound that the extension characteristics of extension force andextension modulus are preferably within defined ranges. The extensionforce preferably is greater than or equal to about 250 grams_(f). it ispreferred that these extension forces be generated at extensions betweenabout 0.25 inches (6.25 mm) and about 1.25 inches (31.25 mm). For themost preferred embodiments, the elasticized side panels preferably havean extensional force between about 250 grams_(f) and about 500 grams_(f)at an extension of between about 0.25 inches (6.25 mm) and about 0.75inches (18.75 mm).

Available stretch measures the maximum amount of material available inthe elasticized side panels to reversibly stretch to conform to thewearer's body during wear. Thus, the amount of available stretch relatesto the maximum amount of extension that the diaperer has available tofit the diaper to the wearer. In addition, the maximum amount ofrecoverable extension available for the diaper to comply with wearer'sbody. The available stretch is calculated from the equation: ((stretchedlength--original length)--original length)×100. The minimum amount ofavailable stretch required for a diaper application using elasticizedside panels is preferably an available stretch of at least about 35% formedium sized diapers and at least about 50% for large sized diapers.

The amount of sustainable contractive force (tension) exerted by theelasticized side panel on the wearer is an Important property of theelasticized side panel. An elasticized side panel with insufficientcontractive forces may result in the diaper slipping down after beingworn and loaded. Excessive contractive forces may reduce the comfort forthe wearer and produce pressure markings on the wearer's skin.Contractive force is measured as the force per unit width produced whilerelaxing an elastomeric composite at a particular extension. Inpreferred embodiments of the present invention, the contractive force ofthe elasticized side panels is preferably at least about 90 grams/inchat 50% extension (a 50% extension would require the sample to bestretched to 1.5 times its original length).

Typical elastomeric materials show a hysteresis loop of force in theirstress-strain property. That is, for a given extension, the force(extension force) required to uniaxially extend the elastomeric materialis greater than the force (contractive force) the elastomeric materialexerts when it is allowed to contract from its pre-extended condition.The former curve can be referred to as the "load curve" and the lattercurve can be referred to as the "unload curve". The "load" extensionforce (extension force) is felt by the diaperer when the elasticizedside panel is stretched to apply the diaper to the wearer. The wearermore nearly "feels" the "unload" contractive forces (contractive forces)once the diaper is on. Therefore, the hysteresis loss should not be sogreat that the contractive force is low enough to allow sagging/slippingof the diaper on the wearer.

All elastomeric materials undergoing sustained stress/strain havediminishing forces with time (i.e., elastic creep). Therefore, it isdesired to make sure this reduction in wearing forces over time doesn'tfall below a minimum for wearing stability. The elastic creep shouldtherefore be kept at a minimum. In preferred embodiments of the presentinvention, the final length of the elastomeric material is not greaterthan about 1.2 times the original length under tension for 30 minutes.

The extension forces and available stretch of the elasticized waistband35 can be important considerations in the performance of both theelasticized waistband 35 and the elasticized side panels 30. While theextension forces of the elasticized waistband 35 may be greater than theextension forces of the elasticized side panels 30, in a preferredembodiment of the present invention, the extension forces of theeiasticized waistband 35 at its designed extensions is less than orequal to the extension forces of each elasticized side panel 30 at itsdesigned extensions. An elasticized waistband 35 having lower extensionforces than that of the elasticized side panels 30 provides for easystomach movement without displacing the diaper on the child. The higherextension force elasticized side panels allow for small dimensionalchanges over the hip and under the stomach to keep the productcomfortably in tension on the wearer. This design provides better fit,less leakage and improved comfort for the wearer through the reductionof sagging, gapping, rollover and roll-in at the front of the diaper andoverall sliding/slipping of the diaper or diaper absorbent core on thewearer during use. As discussed herein, FIG. 6 discloses an alternativeembodiment of the present invention wherein the shaped "expansive tummypanel" preferably has lower extension forces [and/or higher availablestretch] than the elasticized side panels to provide the improvedperformance discussed herein.

The elasticized side panels 30 may also be provided with differentialextensibility along the longitudinal axis when stretched in the lateraldirection. As used herein, the term "differential extensibility" is usedto mean a material having a nonuniform degree of elastic extensionalproperties, as measured in the direction of stretching at various pointsalong an axis oriented substantially perpendicular to the direction ofstretching. This may, for example, include varying the elastic modulusor available stretch or both of the elastomeric material(s). Thedifferential extensibility is preferably designed into the elasticizedside panels 30 so that the lateral extensibility varies longitudinallythrough at least a portion of the elasticized side panel as measuredfrom the end edge 64 of the diaper 20 to the leg edge 106 of the earflap 88. Without wishing to be bound by any theory, it is believed thatdifferential extensibility along the longitudinal axis when stretched inthe lateral direction allows the elasticized side panel todifferentially stretch and conform to the wearer's waist during usewhile providing a secure anchor about the hip of the wearer so as topromote sustained fit and reduce leakage at the waist and legs. Such aconfiguration may allow more "expansion" in the hip area to accommodatechanges in the wearer's body size as the wearer moves and changespositions (standing, sitting, lying). In an alternative embodiment, adegree of reduced lateral extensibility in the portion of theelasticized side panel adjacent to the end edge 64 of the diaper 20requires more of the total extension to be assumed by the elasticizedwaistband 34 thereby resulting in more localized stretching of theelasticized waistband 34 and a more compliant abdominal fit.

The differential extensibility can be achieved in a number of differentways. The elasticized side panels 30 can have multiple combinedelastomeric materials, multiple configurations for the elastomericmaterials, or the extension properties of the elastomeric or othermaterial or materials making up the elasticized side panel may benonuniform. For example, differential extensibility can be achieved inselected adjacent portions of the elasticized side panel by usingelastomeric materials having varying extension or contractive forces,modulus, or other inherent properties such that more or less (varying)lateral extensibility is achieved in one portion of the elasticized sidepanel than the adjacent portion. The elastomeric materials may also havevarying lengths, sizes, and shapes that provide differentialextensibility. Other ways of varying the properties of materials thatform the elasticized side panels as are known in the art may also beused.

A particularly preferred method and apparatus for imparting a varyingdegree of extensibility to a "zero strain" stretch laminate is to passthe "zero strain" stretch laminate through at least one set of meshingcorrugated rolls, at least one of the corrugated rolls havingcorrugations of nonuniform profile along its point or points of contactwith the "zero strain" stretch laminate web. As a result, the portionsof the laminate web passing between the set of rolls are nonuniformlystretched. This, in turn, produces a "zero strain" stretch laminatewhich is nonuniformly elasticized in a direction substantiallyperpendicular to the nonuniformly profiled corrugations.

The diaper 20 is preferably applied to a wearer by positioning one ofthe waist regions, preferably the second waist region 58, under thewearer's back and drawing the remainder of the diaper between thewearer's legs so that the other waist region, preferably the first waistregion 56, is positioned across the front of the wearer. The tabportions 94 of the tape tabs 92 are then released from the releaseportion 95. The diaperer then wraps the elasticized side panel 30 aroundthe wearer, while still grasping the tab portion 94. The elasticizedside panel 30 will typically be extended and tensioned during thisoperation so as to conform to the size and shape of the wearer. Thefirst fastening component 112, the adhesive attachment layer 96, issecured to the second fastening component 114 of the landing member 44to effect a side closure. In the preferred embodiment of the presentinvention, when the side closure is formed, the waist closure is also"automatically" formed, I.e., the waist closure is passively activated.The waist closure is formed by the engagement of the first attachmentcomponents 46 with the second attachment component 48. With theformation of the waist closure, the elasticized waistband 35 ispretensioned so as to provide the fit and containment benefits describedherein.

As shown in FIGS. 4A-4D, the elastic waist feature 34 of the presentInvention moves with and conforms to the waist of the wearer as thewearer sits, stands, or moves such that the end edge is in the samegeneral relation with respect to the navel of the wearer when the wearerstands, sits, or stands after sitting. Therefore, the discussion thatfollows relates the relative motions in relation to the navel. As shownin FIG. 4A, the waistline panel zone 338 contacts the waist of thewearer and snugly fits against the waist as a result of the tensioninduced in the elasticized waistband by the closure system as initiallyapplied. As shown in FIG. 413, as the wearer begins to sit down, theInterconnecting panel zone 130 pivots about the first flexural hingezone 132 and about the second flexural hinge zone 134 to move theelasticized waistband out of the plane that it was originally in. Thewaist edge of the absorbent core tends to move toward the navel. Asshown in FIG. 4C, as the wearer continues to sit down, the absorbentcore is pushed further toward the navel while the interconnecting panelzone 130 tends to flex and fold about the absorbent core. The stomach ofthe wearer also begins to push outwardly to flexurally deflect thewaistline panel zone 138 in relation to the shaping panel zone 136 aboutthe predisposed waistband flexural hinge zone 140. As shown In FIG. 4Dwith the wearer completely sitting down, the absorbent core has pushedto its furthest extent against the belly with the interconnecting panelzone 130 totally flexed against the inner portion of the absorbent core.The shaping panel zone 136 is flexurally deflected to be in contact withthe inner portion of the stomach while the waistline panel zone 138 hasbeen completely pushed and flexurally deflected about the predisposedresilient waistband flexural hinge zone 140 to conform to the protrudingwaist of the wearer. Thus, a snug fit between the elasticized waistbandand the wearer's waist is maintained. As the wearer stands up fromsitting down, the process is repeated in reverse order with theresiliency of the waistband flexural hinge zone 140 providing arestoring force/moment that allows the waistline panel zone 138 tomaintain contact with the waist of the wearer as the wearer continues tostand up, and to return the shaping panel zone 136 and the waistlinepanel zone 138 to their previous in-use (pretensioned) configurationagainst the waist with friction finally pulling the interconnectingpanel zone 130 up into generally its original position with intimatecontact between the elasticized waistband and the waist of the wearer.After several wearing cycles, a condition similar to that shown in FIG.4B becomes the "neutral" position during standing, then all furthermovements of the wearer resemble the cycle shown in FIGS. 4B through 4D.

FIG. 5 shows an alternative construction for the elasticized waistbandof the present invention. The elasticized waistband 535 comprises aportion of the backsheet 26, preferably prestrained; a portion of thetopsheet 24; and an elastic laminate comprising an elastomeric member 76and a facing member 501. The elastomeric member 76 is positioned betweenthe backsheet 26 and the facing member 501 with the topsheet 24 beingpositioned between the backsheet 26 and the elastomeric member 76. Theelasticized waistband 635 is preferably formed by manufacturing thediaper with the topsheet 24 and the backsheet 26 joined together,forming a bi-laminate of the elastomeric member 76 and the facing member501 in a separate step, and subsequently joining the bi-laminatematerial to the topsheet 24 of the combination topsheet/backsheet withthe elastomeric member 76 facing the topsheet 24 so that the facingmember 501 contacts the skin of the wearer. In this embodiment, theelastomeric member 76 is preferably a heat-shrinkable elastomericmaterial as previously described herein. The facing member 501 ispreferably a soft, non-irritating material such as the materialspreviously described with respect to the materials suitable for use asthe topsheet 24. The facing member 501 is preferably a nonwoven materialsimilar to the nonwoven material preferred for use as the topsheet 24.

FIG. 5A shows a further alternative construction of the elasticizedwaistband of the present invention. The elasticized waistband 535 isformed from a portion of the backsheet 26, preferably prestrained; afacing member 501; an elastomeric member 76 positioned between thebacksheet 26 and the facing member 501; a portion of the topsheet 24positioned between the backsheet 26 and the elastomeric member 76; and aresilient member 77 positioned between the topsheet 24 and theelastomeric member 76. The elasticized waistband 535 is preferablyformed from the same materials as previously discussed and in the samemanner as discussed with respect to the embodiment shown in FIG. 5,except that a tri-laminate of the facing member 501, the elastomericmember 76, and the resilient member 77 is formed and then secured to thetopsheet 24.

FIG. 6 shows an alternative embodiment of the diaper and the elasticwaist feature of the present invention. The elastic waist feature 634comprises a relatively high edge compression stiffness interconnectingpanel zone 130 flexurally joined to the containment assembly 22; an"expansive tummy panel" elasticized waistband 635 flexurally joined tothe interconnecting panel zone 130; a first flexural hinge zone 132flexurally joining the interconnecting panel zone 130 with thecontainment assembly 22; and a second flexural hinge zone 134 flexurallyjoining the elasticized waistband 635 with the interconnecting panelzone 130. As shown in FIG. 6, the elasticized waistband 635 has a deep"pentagon" shape to form an "expansive tummy panel". The elasticizedwaistband is longer (longitudinal dimension) to provide for the primaryside closure to be formed below the area of stomach movement. Thelongest dimension of the elasticized waistband 635 (as measured from theend edge 64 longitudinally inward) is preferably between about 38 mm(1.5 inches) and about 88 mm (3.5 inches), more preferably between about50 mm (2.0 inches) and about 57 mm (2.25 inches) for medium-sizeddiapers. This shape provides a waistband that moves and expands with thewearer's stomach as well as differential lateral extensibility such thatportions of the elasticized waistband adjacent the end edge 64 are moreextensible than adjacent portions farther from the end edge 64. Theelasticized waistband 635 comprises a shaping panel zone 136; awaistline panel zone 138; and a predisposed, resilient, waistbandflexural hinge zone 140. The waist edge 83 of the absorbent core 28 isgenerally parallel to the end edge 64 of the diaper (a straight line)and is moved longitudinally farther away from the end edge 64 to providefor the deeper "expansive tummy panel". (In medium-sized diapers, thewaist edge 83 of the absorbent core 28 is preferably positioned betweenabout 50 mm (2 inches) and 57 mm (about 2.25 inches) longitudinally awayfrom the end edge 64.) The diaper embodiment shown in FIG. 6additionally comprises a modified shape landing member 644 of theprimary fastening system, longitudinally longer first attachmentcomponents 646 disposed on the backsheet 26, and a laterally widerpositioning patch 650 positioned subjacent each of the first attachmentcomponents 646.

The elasticized waistband 635 is preferably constructed of a portion ofthe backsheet 26, a portion of the topsheet 24, an elastomeric member 76positioned between the topsheet 24 and the backsheet 26, and a resilientmember 77 positioned between the backsheet 26 and the elastomeric member76. The elastomeric member 76 preferably comprises an elastomeric foamwhile the resilient member 77 comprises a nonwoven layer such as hasbeen previously described herein. The bi-laminate elastomeric materialof the elastomeric member 76 and the resilient member 77 preferablyextends beyond the mechanically stretched edges of the elasticizedwaistband 635 and forms a portion of the interconnecting panel zone 130and a portion of the containment assembly 22 since it preferably extendslongitudinally inwardly beyond the waist edge 83 of the absorbent core28. The overlap of the bi-laminate elastomeric material with theabsorbent core 28 is designed to stiffen the Interconnecting panel zone130 and to reduce the potential for roll-over of the elasticizedwaistband 635 in this embodiment. (In a preferred medium-sized diaper,the overlap between the elastomeric material and the absorbent core isbetween 0 mm to about 6 mm (1/4 inch)). The elasticized waistband 635preferably comprises a stretch laminate so that the elasticizedwaistband is capable of expanding beyond the original planar state ofthe diaper. The elasticized waistband 635 is preferably manufactured bysecuring the elastomeric material between the topsheet and the backsheet(most preferably in a tensioned condition), and mechanically stretching(as hereinbefore described with respect to the elasticized side panels)the portion of the elastic waist feature in the shape desired to formthe elasticized waistband. (i.e., the grooves and lands of thecorrugated rolls correspond to the desired pentagon shape of theelasticized waistband.) This stretch laminate (preferably themechanically stretched, pretensioned, stretch laminate) allows forexpansion of the elasticized waistband well beyond the dimensions of thecircumference of the diaper formed by the primary closure system andbeyond the initial dimension of the end edge 64 (beyond the planar stateof the diaper itself). (I.e., The elasticized waistband is capable ofexpanding well beyond the dimension of the circumference of the fixeddimension of the side closure (even beyond the dimension of thematerials initially forming the diaper) so as to follow the wearer'sstomach movements.) This expansion can also be accomplished by orenhanced (for stretch laminates) by "windowing" the elastic waistfeature.

In this embodiment, the interconnecting panel zone 130 is relativelystiff and has a higher edge compression stiffness than the shaping panelzone 136 and the waistline panel zone 138. (Thus, this elastic waistfeature functions differently than as shown in FIG. 4A-4D.) Thisrelative stiffness of the interconnecting panel zone 130 furtherenhances the ability of the elasticized waistband 635 to expand beyondthe dimensions of the primary side closure. The interconnecting panelzone 130 preferably comprises a portion of the topsheet 24, a portion ofthe backsheet 26, a portion of the elastomeric material comprising theelastomeric member 76 and the resilient member 77, and a portion of thelanding member 644 since the shape of the landing member 644 has beenmodified so as to conform to the shape of the elasticized waistband 635.The landing member also extends beyond the waist edge 83 of theabsorbent core 28 to form a portion of the containment assembly 22. Thelanding member 644 preferably extends well beyond the waist edge 83 ofthe absorbent core 28 to allow lower taping of the primary closuresystem so as to position the primary side closure (the primary tensionline) below the area of stomach movement (i.e., below the lowermostpoint of the elasticized waistband). The top edge (the edge closest tothe end edge) of the tape tab has also been longitudinally positionedfarther from the end edge to accomplish this lower taping. The tape tabis preferably longitudinally positioned about 39 mm (about 1.56 inch)from the end edge in a preferred medium-sized diaper.

The shaping panel zone 136 of the elasticized waistband 635 comprises aportion of the backsheet 26, a portion of the topsheet 24, a portion ofthe elastomeric member 76, and a portion of the resilient member 77, Thewaistline panel zone 138 comprises a portion of the topsheet 24, aportion of the elastomeric member 76, and a portion of the resilientmember 77. The waistline panel zone 138 does not comprise a portion ofthe backsheet 26 since it has been removed in this region. Thepredisposed, resilient, waistband flexural hinge zone 140 is formed bythe structural discontinuity caused by the removal of the backsheet Inthe waistline panel zone 138 (a "windowed" elasticized waistband). Thewindow is at least about 4.5 mm (about 3/16 inch), preferably from about9 mm (about 3/8 inch) to about 16 mm (about 5/8 inch), long and about125 mm (about 5 inches) wide for preferred medium-sized diapers. Thewaistline panel zone 138 is thus able to flexurally bend and deflectabout the area where the backsheet has been removed. (In an alternativeembodiment, the backsheet need not be removed but the pattern of bondingof the materials together would create the predisposed, resilient,waistband flexural hinge zone.) Thus, with the removal of the backsheet,the edge compression stiffness (and the extension forces) of thewaistline panel zone is less than the edge compression stiffness (andthe extension forces) of the shaping panel zone. As previouslydiscussed, the edge compression stiffness of the shaping panel zone isless than the edge compression stiffness of the interconnecting panelzone. It has been found that the edge compression stiffness of thewaistline panel zone is preferably less than about 100 grams_(f), morepreferably between about 20 grams_(f) and about 50 grams_(f), mostpreferably about 35 grams_(f) with the edge compression stiffness of theshaping panel zone being preferably greater than that of the waistlinepanel zone, most preferably about 50 grams_(f). The bending flexurerestoring force of the waistband flexural hinge zone, and preferably theentire elasticized waistband, is greater than about 20 grams_(f), morepreferably between about 40 grams_(f) and about 80 grams_(f), mostpreferably about 60 grams_(f).

Based upon the materials used and the manner of constructing theelasticized waistband, the extension forces at its designed "in-use"extensions are less than or equal to the extension forces of eachelasticized side panel at their designed "in-use" extensions. Theextension forces of the elasticized waistband are less than theextension forces of the elasticized side panels to allow the stomach tomove more with the elasticized waistband as previously discussed herein.Further, the available stretch of the elasticized waistband is typicallygreater than the available stretch of the elasticized side panels. Forpreferred diapers, the extension forces of the elasticized waistband arepreferably less than or equal to about 250 grams_(f) at extensions ofbetween about 25 mm (1 inch) and about 76 mm (3 inches), more preferablybetween about 25 mm (1 inch) and about 50 mm (2 inches). Mostpreferably, the extension forces for the elasticized waistband arebetween about 75 grams_(f) and about 250 grams_(f) at 25 mm (1 inch) toabout 76 mm (3.0 inches) extensions, more preferably between about 25 mm(1 inch) and about 50 mm (2 inches). Since in a preferred embodiment ofthe elastic waist feature, a segment of the backsheet has been removedto form the waistline panel zone, the extension forces of the waistlinepanel zone are less than the extension forces of the shaping panel zone.(The edge compression stiffness is also changed by this windowing.) Theextension forces of the waistline panel zone are preferably betweenabout 75 grams_(f) and about 175 grams_(f) at these designed "in-use"extensions for the elasticized waistband while the extension forces ofthe shaping panel zone are preferably between about 175 grams_(f) andabout 225 grams_(f) at these extensions. Most preferably, the extensionforce of the elasticized waistband in the waistline panel zone is about150 grams_(f) at a 50 mm (2 inch) extension and in the shaping panelzone is about 200 gram_(f) at a 50 mm (2 inch) extension. This is incontrast to the extension forces of the elasticized side panels whereinit is desired that the elasticized side panels have an extension forcewindow of greater than or equal to about 250 grams_(f) at extensions ofbetween about 6 mm (0.25 inches) and about 76 mm (3 inches), morepreferably between about 250 grams_(f) to about 500 grams_(f) atextensions of between about 6 mm (0.25 inches) to about 19 mm (0.75inches).

The positioning patch 650 is disposed in the diaper so as to abut withor extend beyond the side edge 75 of the elastomeric member 76 of theelasticized waistband 635. The positioning patch 650 preferablycomprises the same elastomeric foam material as is used for theelastomeric member 76. In fact, the positioning patch 650 can comprise aportion of the elastomeric member 76 if desired. This disposition forthe positioning patch adds additional stiffness in the first side panels70 to provide a more secure and stiffer panel that decreases the foldingof the first side panel 70 at the crease between the elastomeric member76 and the positioning patch 650. In a preferred embodiment of amedium-sized diaper, the positioning patch overlaps the elastomericmember from 0 mm to about 3.1 mm (1/8 inch).

The first attachment components 46 of the embodiment shown in FIG. 6 arepreferably longer in the longitudinal direction because of the preferredshape of the elasticized waistband, because of the desire to pretensiona greater area of the deeper elasticized waistband, and because of thepreferred lower securement of the primary fastening system in apreferred embodiment for medium-sized diapers, the first attachmentcomponents are preferably about 25 mm (about 1 inch) long.

FIG. 7 shows an alternative embodiment of the elastic waist featureshown in FIG. 6. As shown in FIG. 7, the shape of the waist edge 783 ofthe absorbent core 28 has an arcuate shape. The arcuate shape absorbentcore has ears 700 which extend upwardly beyond the elasticized waistband735 to bound a portion of the elasticized waistband and to furtherstiffen the areas adjacent the elasticized waistband 735 and provideadditional containment.

In a further alternative embodiment, the elasticized waistband is formedsimilarly to that shown in FIG. 2 except that the resilient membercomprising a nonwoven material is interposed between the topsheet andthe elastomeric member rather than between the backsheet and theelastomeric member as shown in FIG. 2.

An alternative embodiment of an elastic waist feature additionallycomprises a waistcap feature. Such a waistcap feature is disclosed inU.S. Pat. No. 4,734,246 issued to Lawson on May 10, 1988 and in U.S.patent application Ser. No. 07/571,000, allowed, Robertson, filed onAug. 21, 1990; each of which are incorporated herein by reference. Thewaistcap would be formed as an extension of the elastomeric material orelastomeric laminate forming the elasticized waistband. The elasticwaist feature would thus additionally comprise a waistcap zone extendinglongitudinally inward from the waist edge of the absorbent core. Thewaistcap zone would comprise a barrier member having a proximal edgejoined to the containment assembly (preferably the topsheet) adjacentthe waist edge and a distal edge capable of being spaced away from (Zdirection) the absorbent core to provide a channel to contain bodyexudates.

FLEXURE BENDING TEST

The flexure bending test uses an INSTRON Model 4502 as available fromInstron Corporation of Canton, Mass., a special displacement "T-rod",and a special test sample holder. As shown in FIG. 11, the "T-rod" 1101comprises a pair of 1/4 inch (6.35 mm) diameter metal rodsperpendicularly mounted together. Preferably, the end of the drive rod1102 (the longer of the rods, being about 125 mm (about 5.25 inches)) istapered to fit the circumference of the push rod 1103 (the shorter ofthe rods, being about 75 mm (about 3 inches)) and the two are glued,welded and/or screwed to each other. The opposite end of the drive rod1102 is mounted to the crosshead unit of the INSTRON. The test sampleholder 1104 comprises a fixture base 1105 to position and support thesupporting rods 1108. The fixture base 1105 comprises a base 1106 andtwo rectangular supports 1107 mounted in parallel on the base 1106. Thebase 1106 and the supports 1107 are each preferably made of LEXAN(plexiglas) plate of about 1/2" to 3/8" thickness. A supporting rod 1108(same material as the "T-bar" and about 150 mm (about 6 inches) long) ismounted on each support 1107 of the fixture base 1105. The supportingrods 1108 are mounted so as to be spaced 16 mm apart, center-to-center.As shown in FIG. 11, the "T-rod" 1101 is centered between the supportingrods 1108.

The INSTRON is set for a crosshead speed of 20 mm/min, a chart speed of400 mm/min, and with full scale at 500 grams_(f). The INSTRON is set upso that the crosshead unit will travel 6 mm down and back, with thechart to follow the crosshead unit down and back.

As shown in FIG. 10, the sample 1000 to be tested is taken from theelastic waist feature 34 so that the waistband flexural hinge zone 140is preferably centered within the sample 1000, although some samples maynot have the waistband flexural hinge zone centered. The sample 1000 isat a minimum 16 mm long (longitudinal direction), preferably 25 mm orany length available, and 50 mm wide (lateral direction.) As shown inFIG. 11, the sample 1000 is centered on the supporting rods 1108 so thatthe waistband flexural hinge zone 140 will be directly under the T-rod1101. The outer surface of the sample 1000 (typically the backsheetside) is placed toward the T-rod 1101.

The T-rod 1101 is "zeroed" on top of the sample 1000 with a lightpreload of a few grams (1 to 4 grams_(f)). This takes out any bowing ofthe sample and insures good contact of the T-rod with the sample. Eachsample is run through the 6 mm travel cycle twice, with a 30 second stopbetween cycles. A total of ten samples are run.

A graph of T-bar deflection force (grams_(f)) versus T-bar deflectiondistance (mm) will be generated. A representative run of a sampleshowing the two cycles is shown in FIG. 12. The deflection force at 4 mmand 5 mm, for each cycle, is determined on the recovery force curve. Therecovery deflection force at 4 mm and 5 mm are averaged to calculate acycle recovery deflection force. The average of both cycle recoverydeflection forces for each sample determines the sample recoverydeflection force. The bending flexure recovery force for the structureis the average of the value of the sample recovery deflection force forthe 10 samples.

EDGE COMPRESSION STIFFNESS TEST

The edge compression stiffness test uses an INSTRON Model 4502 asavailable from Instron Corporation of Canton, Mass., a special testsample holder, and mounting adhesive. As shown in FIG. 13, the samples1002 are mounted to a 1 inch (25 mm) by 2 inch (50 mm) by 1/16 inch(1.56 mm) aluminum flat plate 1300 by the mounting adhesive 1302. Themounting adhesive 1302 is a quick set epoxy as available from HartmanAdhesives of Belleville, N.J. and marketed as Red-04001 double bubblepacks.

The INSTRON is provided with a compression load cell. (The load cell andthe INSTRON jaw flat plate should be checked for flatness andsquareness.) The INSTRON is set for a crosshead speed of 5 mm/min., achart speed of 250 mm/min., and full scale of 100 or 500 grams (asneeded). The cycle length is 3.5 mm down and back, with the chart tofollow the crosshead unit down and back.

As shown in FIG. 10, the sample 1002 to be tested is taken from theelastic waist feature 34 in preferably the waistline panel zone 138 orthe shaping panel zone 136 or the interconnecting panel zone 130depending upon which zone is to be tested. The sample 1002 is 9 mm inlength by 25 mm wide.

The mounting adhesive 1302 is spaced on the plate 1300 using a doctorblade to make a footprint approximately 3/8 inch (8.5 mm) wide and aheight of 0.020 inch to about 0.030 inch (0.5 to 0.75 mm). The sample1002 is placed in the mounting adhesive 1302 and held perpendicular tothe plate 1300 with blocks on either side of the sample. These blocksare relieved at the base so that they will not get into the mountingadhesive. After the mounting adhesive has been given some time to set(approximately 1 minute or more), the mounted samples are placed in a73° F./50% relative humidity room for about 24 hours or overnight sothat the mounting adhesive can fully set.

The mounted samples are placed on the lower jaw 1400 of the INSTRON asshown in FIG. 14. The samples are preloaded with a 1 to 4 grams_(f)preload to zero the INSTRON. Each sample is run through a 3.0 mmdeflection cycle twice, with 30 seconds allowed between the cycles. Fivesamples are tested.

A graph of compression force (grams_(f)) versus compression displacement(mm) will be generated. A representation run of a sample showing the twocycles is shown in FIG. 15. The peak force for the run is measured asthe highest force generated during both cycles. The average of the peakcompression forces for the five samples is the edge compressionstiffness of the zone.

EXTENSION FORCE TEST

The extension force test for both the elasticized side panels 30 and theelasticized waistband 35 uses an INSTRON Model 4502 as available fromInstron Corporation of Canton, Mass.

A. ELASTICIZED SIDE PANELS

The INSTRON is set for a crosshead speed of 100 mm/min, a chart speed of500 mm/min, and with full scale at 1000 grams_(f). The INSTRON will beallowed to travel the desired, claimed, or full elastic extension of theside panel. (If the full extension of the side panel is less than theupper limit claimed, then the test is stopped at this extension sincethe extension forces at nonextensible areas should not be taken intoaccount; i.e., the designed in-use extension limit has been reached.)

The sample to be tested is determined on the actual diaper itself. Astandard 3 inch (75 mm) clamp is attached to the elasticized side panel30 adjacent the edge of the activated stretch portion of the side panellaterally closest to the longitudinal centerline 67. In most situations,this edge corresponds to the side edge 91 of the elastic side panelmember 90. A standard 1 inch (25 mm) clamp is attached to the oppositeedge of the activated stretch portion of the elasticized side panel 30(typically the side edge 91' of the elastic side panel member 90). The 1inch clamp is positioned so as to be within the area of the 3 inch clampand longitudinally aligned with the component of the primary fasteningsystem 38 positioned adjacent the elasticized side panel 30. Thus, In apreferred embodiment, the 1 inch clamp is longitudinally aligned withthe securement member 42, tape tab 92, so that the force applied by theINSTRON is similar to the force applied by the user when applying thediaper.

Each sample is run through a travel cycle to the designed, claimed, orfull extension of the activated elastic portion of the elasticized sidepanel. (The sample may be allowed to contract to also measurecontractive force.) A graph of extension force (grams_(f)) versusextension (mm) will be generated. A total of ten samples are run. Theextension force at a given extension is the average of the values forthe 10 samples.

B. ELASTICIZED WAISTBAND

The INSTRON is set for a crosshead speed of 500 mm/min, a chart speed of500 mm/min, and with full scale at 500 grams_(f). The INSTRON will beallowed to travel the desired, claimed, or full elastic extension of thewaistband. (If the full extension of the waistband is less than theupper limit claimed, then the test is stopped at this extension sincethe extension forces at nonextensible areas should not be taken Intoaccount; i.e., the designed in-use extension limit has been reached.)

The sample to be tested is taken from the elasticized waistband 35,preferably adjacent the upper edge of the elasticized waistband (exceptwhere specific panel zones are to be tested). The sample is preferably25 mm (1 inch) long (longitudinal direction) and about 125 mm to about150 mm wide lateral direction) so that a sample width of 100 mm (4inches) is tested. If the elasticized waistband 35 or the panel zone tobe tested is less than 25 mm (1 inch) long (longitudinal direction) sothat a 25 mm (1 inch) sample cannot be obtained, the test may be carriedout using this modified size sample although this is not a preferredsituation. The ends of the sample are clamped using standard 1 inch (25mm) clamps with 4 inches (100 mm) between the clamps. (No zones or areasof the sample should be nonextensible excluding bond sites).

Each sample is run through a travel cycle to the desired, claimed, orfull extension of the elasticized waistband sample. (The sample may beallowed to contract to also measure contractive force.) A graph ofextension force (grams_(f)) versus extension (mm) will be generated. Atotal of ten samples are run. The extension force at a given extensionis the average of the values for the 10 samples.

While particular embodiments of the present invention have beenillustrated and described, it would be obvious to those skilled in theart that various other changes and modifications can be made withoutdeparting from the spirit and scope of the invention. It is thereforeintended to cover in the appended claims all such changes andmodifications that are within the scope of this invention.

What is claimed is:
 1. A unitary disposable absorbent articlecomprising:a containment assembly having longitudinal edges, an end edgelocated in a first waist region, and an end edge located in a secondwaist region opposed to said first waist region, said containmentassembly comprising a topsheet, a backsheet joined with said topsheetand an absorbent core located between said topsheet and said backsheet,said absorbent core having side edges and waist edges; and anelasticized side panel disposed in said second waist region of saidcontainment assembly adjacent each said longitudinal edge, each saidelasticized side panel extending longitudinally from said end edge ofsaid second waist region to a leg edge, each said elasticized side panelcomprising a first nonwoven layer and an elastomeric scrim joined withsaid first nonwoven layer to form a laminate, said laminate disposedbetween said end edge of said second waist region and said leg edge ofsaid elasticized side panel, said laminate being mechanically strainedto provide a zero strain stretch laminate in said side panel such thateach said elasticized side panel is elastically extensible in thelateral direction.
 2. The absorbent article of claim 1 wherein saidbacksheet extends laterally outwardly beyond said longitudinal edges ofsaid containment assembly in said second waist region such that saidfirst layer of said side panel comprises a portion of said backsheet. 3.The absorbent article of claim 2 wherein said backsheet comprises anonwoven web.
 4. The absorbent article of claim 3 wherein said topsheetextends laterally outwardly beyond said longitudinal edges of saidcontainment assembly in said second waist region such that each saidside panel additionally comprises a portion of said topsheet.
 5. Theabsorbent article of claim 4 wherein said topsheet comprises a nonwovenweb.
 6. The absorbent article of claim 1 wherein each said elasticizedside panel is a separate element joined to said containment assembly. 7.The absorbent article of claim 1 wherein said laminate of said firstnonwoven fibrous layer and said elastomeric scrim further includes aresilient member.
 8. The absorbent article of claim 7 wherein saidresilient member includes an apertured film.
 9. The absorbent article ofclaim 1 wherein said elasticized side panels are integral with saidcontainment assembly.
 10. The absorbent article of claim 1 additionallycomprising a closure system positioned on the absorbent article, saidclosure system comprising a primary fastening system comprising aclosure member disposed on each said elasticized side panel and at leastone landing member disposed in said first waist region on saidcontainment assembly, said closure members and said landing member beingengageable with each other.
 11. The absorbent article of claim 10wherein said primary fastening system is a mechanical fastening systemof the hook and loop type.
 12. The absorbent article of claim 10 whereinsaid closure system additionally comprises a waist closure systemcomprising at least one first attachment component disposed in saidfirst waist region and at least one second attachment component disposedin said second waist region, said second attachment component beingengageable with said first attachment component.
 13. The absorbentarticle of claim 12 wherein said primary fastening system and said waistclosure system each comprise a mechanical fastening system of the hookand loop type.
 14. The absorbent article of claim 10 or 12 wherein eachsaid closure member comprises a tape tab joined to said elasticized sidepanel.
 15. A unitary disposable absorbent article comprising:acontainment assembly having longitudinal edges, an end edge located in afirst waist region, and an end edge located in a second waist regionopposed to said first waist region, said containment assembly comprisinga topsheet, a backsheet joined with said topsheet and an absorbent corelocated between said topsheet and said backsheet, said absorbent corehaving side edges and waist edges; and an elasticized side panelextending laterally outwardly from each said longitudinal edge in saidsecond waist region, each said elasticized side panel extendinglongitudinally from said end edge of said second waist region to a legedge, each said elasticized side panel comprising a first nonwovenlayer, a second nonwoven layer and an elastomeric scrim joined betweensaid first nonwoven layer and said second nonwoven layer to form alaminate, said elastomeric scrim located between said end edge of saidsecond waist region and said leg edge of said elasticized side panel,said elastomeric scrim extending from a location longitudinally inwardlyof said waist edge of said absorbent core to a location longitudinallyoutwardly from said waist edge of said absorbent core in said secondwaist region, said laminate being mechanically prestrained to provide azero strain stretch laminate in said side panel such that each saidelasticized side panel is elastically extensible in the lateraldirection.
 16. The absorbent article of claim 15 wherein saidelasticized side panels are integral with said containment assembly. 17.The absorbent article of claim 15 wherein said elasticized side panelsare separate members joined to said containment assembly.
 18. Theabsorbent article of claim 15 wherein said backsheet extends laterallyoutwardly beyond said longitudinal edges of said containment assembly insaid second waist region such that said first layer of said side panelcomprises a portion of said backsheet.
 19. The absorbent article ofclaim 18 wherein said backsheet comprises a nonwoven web.
 20. Theabsorbent article of claim 19 wherein said topsheet extends laterallyoutwardly beyond said longitudinal edges of said containment assembly insaid second waist region such that each said side panel additionallycomprises a portion of said topsheet.
 21. The absorbent article of claim20 wherein said topsheet comprises a nonwoven web.
 22. The absorbentarticle of claim 15 additionally comprising a closure system positionedon the absorbent article, said closure system comprising a primaryfastening system comprising a closure member disposed on each saidelasticized side panel and at least one landing member disposed in saidfirst waist region on said containment assembly, said closure membersand said landing member being engageable with each other.
 23. Theabsorbent article of claim 22 wherein said primary fastening system is amechanical fastening system of the hook and loop type.
 24. The absorbentarticle of claim 23 wherein said closure system additionally comprises awaist closure system comprising at least one first attachment componentdisposed in said first waist region and at least one second attachmentcomponent disposed in said second waist region, said second attachmentcomponent being engageable with said first attachment component.
 25. Theabsorbent article of claim 24 wherein said primary fastening system andsaid waist closure system each comprise a mechanical fastening system ofthe hook and loop type.
 26. The absorbent article of claim 22 whereineach said closure member comprises a tape tab joined to said elasticizedside panel.